# Gun & Pike Era Orc army and tactic

Probably beginning of a series of questions.

Human armies

I treat human as comparison point for other races. Their civilization level is around ~1500-1550 year of our world. Heavy cavalry is still used and prominent and knights are still most important part of it. Infantry forces are based on early tercio, where 1/3 have arquebus, 1/3 pikes and 1/3 swords. Small amount of artillery is used in battle but they're not that practical and their main task is to break walls in siege.

Orcs characteristic

• orcs are bigger and stronger than humans
• they can eat almost anything and cover big distances in short amount of time thanks to less complicated logistic and endurance
• they aren't less intelligent but more aggressive. They have less advanced technology but it's caused by lack of education and mostly nomadic lifestyle in past
• cultural life is focused around fighting with exception of shamans. Shamans are source of knowledge and divinations and only most popular warbosses earn more respect than them
• they breed faster than humans but population growth is limited by available resources
• orcs like to keep things close and personal, so melee combat is preferable for them
• economy is primitive, focused on pillaging things. Orcish tribes can create goods to sustain not so big population and arm it, but their manufacturing is inferior to humans

Orcish tribes and history

During antique era, orcs were equivalent of barbarians. They controlled large territories but were scattered. From time to time prominent warboss assembled horde which could ravage large territories, destroy smaller countries or significantly weaken empires but lack of internal stability didn't allowed to create long existing countries.

Medieval era was harsh for them, as humankind started to thrive and in a long series of conflicts was able to force orcs to abandon most of their territory and withdraw to non fertile steppes and mountains. Their defeat was caused mostly by successful usage of divide et impera tactic by humans and battles was won with one with more powerful forces or better tactic.

Currently orcs are more of annoyance than real danger, as they perform raids, but many of them are repelled.

Orcs fight a lot between tribes, but it's not total war - lost army can retreat, their village is looted (but without much civilian killing), useful people are allowed to switch sides. This allow them to maintain their military prowess without annihilating themself. They're merciless for other races through, burning whole cities and killing or enslaving population.

Most important for tribes are shamans, which provided spiritual guidance and acted as oracle. Shaman prophecies are important. Lost of shaman could shatter tribe, but they didn't have direct political power and most of them wasn't really interested in it. Their spiritual connection with rest of tribe means that they're focusing on tribe well-being (at least in way they understand as well) and more intelligent shamans could use their power in selecting warbosses (or even creating "false" prophecies) to provide good leadership.

Tribes are ruled by warbosses, selected from most prominent fighters by shaman. Best warbosses are not only great fighter but also tactician. They handle absolute power but it's based around them. I would see analogy in hordes leadership - great warboss can lead it tribe to subjugate other tribes and create hordes which are very dangerous and powerful but shortliving.

Orcish army in medieval

Orcish army was based on heavy infantry as their strike force, many of which was using ravaged equipment of other races as it was much better. Light infantry used orcish equipment, mainly easy to create spears, axes and maces.

Ranged infantry was scarce. No crossbows, archers were quite rare. Orcs relied on skirmishers which were joining hand combat when they ammunition was depleted.

No cavalry.

With warboss who is bad tactician orcs armies aren't that dangerous and their tactic is mostly based on charging enemy.

Things changes with skilled warboss, who are able to utilise orcs strengths to perform manoeuvrers similar to Napoleonic Warfare. Divided forces can cover big distances to join on field of battle and flank enemy. Skirmishers often were used as flanking forces, supported by spearmans if needed, to allow them to throw their weapons in back of enemy forces and engage in melee.

They're bad at sieges but they can take castles appearing from nowhere and taking down unprepared defenders.

World

There might be some metals that could be used in alloys which would give better armour and weapon than steel but they should be scarcely enough to equip only elite forces with it.

Magic was once here, but I would prefer it to be unavailable in this era. Magic was mid level with some powerful but dangerous and hard to cast combat spells. It was more effective than medicine in healing. There can be some artifacts (level like "this sword is cool, slice easily and gives me more strength and endurance" or magically enhanced armor which is way more efficient) from last times but they are scarce and for most people it's more of a myth.

Ok, so now I can go to question itself ;)

How genius warboss (Napoleon level, someone who can reform army and country in a way that changes how wars are waged and countries ruled) should reform his army and tactic to be able to defeat more advanced and better equipment armies with what he has?

• orcs can get gunpowder weapons and utilise them, but not as effective as humans nor dwarfs. They can't, at least at the begging, produce neither weapon nor ammunition and gunpowder but they can rely on capturing it.
• their tactic can be suited strictly for mountain warfare, but it would be great for a way for them to win battles on plain terrain despite enemy range advantage
• if some things given in question makes it impossible to answer, you can change it and provide solution. Nothing is written in stone so I can change stuff ;)
• Are you asking how an orc warboss can defeat the humans? Dec 20 '19 at 13:04

Short answer - orcs should become more organized than humans, and abuse feudal rivalry properly to capture human lands, while reducing peasant human causalities to minimum, to firstly force peasants work for them, and later, make peasants willingly work for Orcs for fair payment. Anyway, i have Christmas vacation, so i decided to write a long answer. I assume orcs are traditional - strong, muscular and bulky green humanoids, but, "they aren't less intelligent but more aggressive (than humans). They have less advanced technology but it's caused by lack of education and mostly nomadic lifestyle in past", and they have Shamans with some mystical powers.

Short excerpts from "Why Orc strong and Human weak" - book written by Orcs Shamans, printed on fine sheepskin (and, sometimes, on skin taken from executed human outlaws, exiled orcs and corrupted officials) and distributed among all Orcs settlements by order of WarBoss-of-WarBosses Doldon the 47th(let the GodMother warms his footprints). This book is translated to Humans language, and every infant (both human and orc) should read this book. And every Warboss and Humans' governor should have this picture of Great Doldon the First WarBoss-of-WarBosses at his or her chambers:

1. Orcs are strong, because we have pretty ladies. Humans don't Just take a look at this sexy pointy ears of this hot babies.
Even if you cannot distinguish, which ones of this 4 orcs are males, and which one is females, its ok. Humans has issues distinguishing orcs. But our ladies like to born children more, than human ladies do. And its easier for them, since infant orcs are smaller than human infants, usually there is 4-5 ones per single birth. So, if there is plenty of food, orcs breed faster than humans. And humans even kill their ladies if they think they cheat with other humans. We don't understand it. Lady is not slave, she belongs to herself only. Also orc ladies loves to fight alongside their man, while humans thinks ladies should never touch weapons, and strong human ladies are not physically attractive. Also we do not burn ladies, if we suspect them in witchery.

2. Orcs are strong, because we have strong stomach, humans don't. Its honour to donate your flesh to feed your tribe after you die, its honour to eat fallen enemy, both for yourself, because it shows you are strong, and to your enemy, because they did not rot in soil feeding unworthy pests. And, humans are too whimsical and capricious in choosing what to eat. Humans can even catch tummy worms from eating raw meat. Orcs cannot.

3. Orcs are strong, because we have good Shamans. Humans are weak, because they have corrupted clergy Shamans picks strongest and smartest orcs, and makes them War-bosses. This War-bosses usually pick fights with weaker tribes of other orcs. Long time ago, we had bad Shamans, they cannot listen to Songs of GodMother properly, and orc tribes battles usually resulted in many orcs killed. Humans easily exiled us to mountains and arid plains with little food. We were on edge of extinction, but miracle happened. GodMother fixed our Shamans to understand Her songs properly, also Shamans learned to scream silently to each other, so they can talk, even if they are separated by great distance. Humans call it telepathy. Humans like to invent fancy words to explain things they do not understand. We don't. Now, if 2 tribes want to fight, their Shamans has council first. Than Shamans takes one random orc from every 10 ones of each tribe, or even one of 100 if tribes are big (because GodMother controls, who is lucky, and who is not), and then this decimated warbands fight under leads of their Warbosses. Sometimes there are fights between 2 Warbosses only or two Warbosses and their children, while their tribesman only make bets. They fight, until any warboss is killed. Than struggle stops, and survived Warboss becomes leader of two tribes. Two tribes joined in new one. So, instead of Dark Bears and Bloody Wolfes tribes, there is new tribe - Bloody Bears. With one Warboss. All orcs had to deny their past and join in new tribe. In worst case, each tribe has every 10th orc lost. So, current tribe struggle is nothing compared to old times when we had bad Shamans - because old vendetas lasted for centuries until last orc died. And current struggles makes tribes united with few orcs lost. Good Shamans educated us to be merciful, to spare lives of our enemies.

And humans are weak, because they have corrupted clergy. Clergy says good things, but secretly does the opposite. Clergy cannot silently scream to each other. Clergymen cannot listen to songs of GodMother. They make feasts when peasants starve. They make orgies while requiring to celibate. They lie. They serve Knights and Barons by pacifying peasants and motivating them to work in promise for good afterlive in the Land of Dead (while very few of clergyman believes in it).

1. Orcs are strong, because Shamans listens to Songs of GodMother to find WarBoss-of-WarBosses among other orcs. Humans are weak, because they listen to themselves. GodMother sends Her most bellowed sons and daughters to make tribes work together and make things they cannot do on their own. Every WarBoss should consider it a honour to serve WarBoss-of-WarBosses. Even if WarBoss-of-WarBosses was not the strongest and smartest one, even if Warboss-of-WarBosses do not believe in his/her path, but it is GodMother who chosen him or her. And Shamans educate Warboss-of-WarBosses to move his Path. To fullfill his Fate. To Unite Orcs. Any WarBoss who refused to serve WarBoss-of-WarBosses, was cursed by Shamans and become exile. And even the youngest orc knows exiles are considered feast food for celebrations! If WarBoss-of-WarBosses is killed or dies, its not an issue, because GodMother is wise. She already send few backup WarBoss-of-WarBosses Shamans are aware off, and Shamans can easily promote any backup one to next WarBoss-of-WarBosses. WarBoss-of-WarBosses makes WarBosses fight together, WarBosses make orcs fight together. WarBoss-of-WarBosses brings order among orcs. For humans - its nearly impossible for King to control other humans. They say - "My vassal's vassals are not my vassals". Humans fight each other too much. And if King dies, there is dramatic rivalry among his children to choose who will be the next King. So, Humans cannot make big things like Orcs can do. Humans are selfish. Orcs are not.

2. Orcs are strong, because they show Mercy. Humans do not Even pre teen orc girl can kill adult Human with bare hands. But is it worth it? Human is tasty, you can make brief dinner for few orcs from him. But, if you butcher cow, you can make feast for much more orcs. Cows meat is beafy. Tastier one. And cow is easier to breed, and even human slaves can do it for you. So, why not eat cows and make humans do the work? If you make human slave, he/she can make things for you - grind your axe, grow crops (yes, they taste terrible, but they are edible), catch fish for you, make your armour and shield, build roads, wagons, ships etc... Human slave can make all boring things Orc considers unworthy. Human has little nimble fingers, Orc do not. But Orcs can make human work for them, and humans - cannot do Orcs works for them. Orcs can convince (without unnecessary violence), Humands cannot. But human slaves are lazy - they don't like to work, and they are cunning, they always plan to flee. Humans are bad slaves. But can we make Humans good slaves? Yes, if we can give them some grade of freedom and respect. Totally yes, if we use their weaknesses properly. And what can we say for humans? If they enslave orcs, they treat them worse than cattle. Barons sometimes treat peasants worse than hunting dogs!

3. Orcs are strong, because they know great weakness of Humans. Humans are greedy. Orcs - not. If you kill Baron and plunder his castle for golden coins and other fancy things Humans like (and Orcs not are interested in), you can give this trinkets to peasants of this Baron in exchange of crops and cattle. Instead of Baron, Orcs are not interested in hoarding shiny little things, so Orcs want less. And after some time, peasants will learn, that Warboss and his Orcs gang are much less trouble than Baron and his knights. Yes, Orcs are noisy and smelly, and Humans are easily offended, but after some time Orcs will only leave Barons castle to punish outlaws, guard trading caravans and collect taxes. On the same time, warband of 100 orcs is easily to sustain than Humans warband of 100 knights. We are not greedy, we don't need decorated armours, golden trinkets and expensive swords and warhorses. And we are not interested in PFclcDb (hard to translate) physically attractive human teenagers like Baron used to do. Orcs warband offers better protection from outlaws, rival Barons and other Orcs tribes. Orcs brings order, order bring peace. All loves peace, order and justice. No matter who brings it - human or orc. When Warboss-of-Warbosses Doldon the 3rd was simple Tax Collector, and human governor tried to trick him, explaining they had famine and they did not have any food and spend all gold on buying supplies, Doldon dealed with it. Everybody was waiting for Doldon to burn castle and village and brutally kill governor, but, instead of it, Doldon showed Mercy. He put governor on leash like dog, and, alongside with villages, pillaged governors castle, forcing governor to show where he hides his stashes of gold and other shiny trinkets. Half of governors belongings was taken as taxes and other distributed among peasants as compensation. After this, governor was forgiven, he was restored in his rights, and, since this time, he and his children became one of best governors. They stopped stealing part of values they should pay as taxes to Warbosses. And, this is how GodMother showed both Orcs and Humans how things should be done.

4. Orcs are strong, because we are good fighters, and we fight together. Humans are not. They fight for themselves. We fight, because we love it, and we love GodMother, we fight in honour of GodMother. And to make future Orcs proud of us. Humans are weak, because they fight mainly for pride, power and gold. Humans fight for their Ego. For their selves. Good Shamans explained it to us, and this is why we win. We did not destroy human civilization. Humans are peasants, clergymen and knights. We took place of knights, because we are better protectors for peasants. And peasants are not fighters, they happily work for ones, who demand less. Usually we made siege for Barons castle. All peasants usually hide in woods nearly. Its ok, we are not interested in killing them. We are more interested in making Baron surrender, or, at least, killing Baron and plundering his castle. And it is easy.

We, orcs, are good at paying human traitors. We are not greedy. And human traitors sometimes betray their human masters not because of money, but because their masters are unworthy, unfair and disrespectful. They tired of their human masters. Even if this idea looks like nonsense for our blood thirsty nature, but best fight is the one, that have not happened. If your enemy decided to surrender or become your ally, its best outcome.

Orcs are good at waiting when Barons castle protectors starts to starve. Its important to make some save passages. So, if any of castle protectors leaves castle, throws away his/her sword, we, Orcs, should allow him or her to leave with peace. Humans knows it. It greatly demotivates castle protectors to fight until death. Sometimes, protectors of human castles surrenders their castles without fight, after few weeks of siege. Its worth notice, that we should show them Mercy. Dead human is feast for few, but living human can be good slave or even loyal worker.

If castle protectors are to stubborn, and we are short in time, we, Orcs, are good in digging. We dig underground passages and castle walls collapses. And, of course, we, Orcs are good at killing and eating knights. And other Barons usually hated each other, so, while we are making siege to Baron's castle, other ones prayed to their gods that we don't assault their castles. Barons unlikely to help their troubled kin. And its only matter of time when we siege their castles.

Sometimes we had really big fights with joined armies of few Barons. Its the time WarBoss-of-WarBosses helped. GodMother (via Shamans) explained him how to make Lines. Connecting things. It include art of making passages, art of sending scouts. How to send orders and reports asking Shamans to silently scream to each other. How to pay human traitors. Humans calls it Logistics, Tactics, Reconnaissance, Communication and Soft Force. So, we always was aware where humans are and what they planned, and we always gathered proper number of warbands at place required, so we nearly always outnumbered human armies. We had feast before fight, and humans was usually hungry and after long walk.

When fight begins, humans used archers - but we had big shields arrows cannot penetrate, and orcs skin is thick - archer had to be lucky.

Crossbowmans caused some trouble, but they are few, because crossbow is expensive to make and crossbowman needs lot of training to aim properly to land bolt in viewing holes in our shields. Yes, we, Orcs, are good at running in heavy armor while carrying our shields in front of us to protect from arrows, bolts and stones.

Pikemen was dangerous. Especially when they guarded archers among the fromations. But we find out we can throw big sticks and stones, bee hives (Bees stings cannot pierce Orc skin), or even jars with incredibly smelly lavatory contents to distract and demoralize pikemen and archers formations. Later we used slingers or portable catapults like this one, which are easy to install, pickup and use in other place

When humans send Knights on horses with long spears, we used our bear sticks. They are longer than spears. If you put one end of bear stick to ground and point sharp end to Knight's horse, horse usually has it chest pierced, and its easy to stomp to death fallen knight with our metal cowered boots and maces. No mater, if our weapons cannot pierce through plate armour, if we bend armour enough, knight inside will die.

If human send heavy infantry, we usually surround and crush them. Swords are not effective against us. Our skin is thick, our armours are bulk and heavy, shields are big and we can pick and throw stones. And we use big and heavy axes and maces majority of adult human cannot even carry in hands. So, even handfull of orcs can deal with few dozens of heavy infantryman without aid of archers and knights.

There were also stories and few cases involving either spellcaster humans, or heroes with magical weapons, capable of killing orcs single handed. But, this stories are probably tales. Barons hires Bards to tell this tales to motivate cowardly knights to fight. In reality, it was little problem. We found few rune cowered swords that "slice easily and gives me more strength and endurance" or found knight in "magically enhanced armour", we cannot either break this armour, or disassemble it, or harm human inside it in any way, so we had to simply drew this knight in improvised warband lavatory.

Majority of spell casters can only make tricks to entertain peasants to make them share food with spellcasters. Yes, there was few spellcasters capable of throwing fireballs big enough to burn castle to ashes. But they can throw maximum few fireball per day (and they had to eat rare magic mushrooms, perform fasting and meditations for week to gather enough mana to make spells), and they was mainly hired by Barons to burn each others castles. The only documented case of usage of magic in Humans to Orcs was was performed by Durga, 21th Warboss-of-Warbosses. She seduced and hired one of this spellcasters to break fortifications of King Roland The Grumpy. It was much faster, than making siege to King Rolands castle. Furthermore, when humans invented boom sticks, spellcasters become obsolete. Using boomstick and boom powder was much cheaper than hiring spellcasters, and spellcasters became obsolete. Few become outlaws, and their trade was forgotten.

Human healers has "magic that was more effective than medicine in healing." But this magic can do nothing when properly beaten knight looks like blob of bent armour with flesh and bones insight. So, this healers was mainly hired or forced to heal Orcs, and, when Shamans learned their trade, they become obsolete, they only had trade as travelling healers and herbalists to heal various old man illness of peasants, and receive payments in food.

We had few naval battles too. We used really big ships our human slaves and hired craftsman build for us. We used long paddles to make them swim fast and ram humans ships.

Sometimes humans used big boom sticks. But it was pathetic. Boom stick is build to ruin castles. We don't build castles. And our warbands do not attack in well organized battle orders, so even if you manage to kill few Orcs with with boom stick blast, other Orc will not stop. And when you reload your boomstick, we will be close enough to tear your arms.

Sometimes humans send sneaky assassins and Death Monks with poisoned blades and dark arts of killing by punching special spots on bodies to kill WarBosses. Assasins usually was hired to kill rival Baron. They mainly succeeded. But it was ineffective for orcs. Because, we, Orcs are physically attractive, and humans are not. Physically attractive orcs do not need fancy clothes and decorated armors to look awesome. And humans does. Physically attractive orcs do not need solitude, if there is few dozens on orcs including Shaman and Warboss sleeping in one dinning room in castle, they feel comfortable, they don't need to hide from each others like humans do because they had ridiculous things like inferiority complex, body shamming and convenances.

So, even if assassin manage to sneak into sleeping chamber, he will have issues finding the right orc he was hired to kill. Orcs are physically attractive, so they all looks the same to humans. Also assassins will have breathing issues, because Orcs smell good, and humans do not.. Even if Death Monk manages to reach Warboss and press right point on his belly, Orc is unlikely to diy. Orc is not human, vulnerable place for humans is likely to be covered in few inches of body fat in orcs body. Because Orcs are physically attractive! Even if nearly miracle coincidence happens and assassin kills the right orc, its not an issue. Next morning Shamans will promote other Warboss.

There was few cases when Assassins was hired to kill shamans. But they never succeeded because, how can you sneak undetected to Shaman, who can hear ants talking under his bed, while he is sleeping? How can you win fight with Shaman, if he is always surrounded by other ors? Even if Assasin catch Shaman when he is listening to Songs of GodMother in solitude, what can Assassin do against him or her? Shamans are guided by GodMother, they can dodge arrows, see invisible, hear silent, predict opponent moves, sniff poisons. Even senior age orc can outrun majority of humans. Assassins never succeeded in killing Shamans. And if after torture Assassins reveal name of person who hired them, the punishment will be fast, imminent and legendary. Killing Shaman is offending GodMother!

Humans learned it fast, that fighting us is hard. And because humans are cowards, they are not very eager to fight with us. And, here is our main, and probably, most powerfull weapon strikes! And, we, Orcs, showed Mercy. We spared live if humans surrendered to us, and we even allowed them become our slaves on long leash until they show their loyalty, and after it, they even was paid in gold trinkets according to work they have done. And sometimes we released slaves, and allowed them to travel to kingdom we want to conquer, to praise how our Shamans are wise, and Warbosses merciful to humans who want to willingly work for Orcs. So, in general human, do not wanted to fight with us. And best struggle is the one, that did not happened, even if this sounds like nonsense to orcs. Later, we, Orcs, make clergyman work for us. Shamans explained them that our GodMother is Mother of humans gods too, and its ok for human to serve Orcs as masters. Its the reasons why we allow clergyman to perform their rituals and chants at their temples. They serve our purpose. In exchange, we still allow them to have their secret pleasures and save some donations peasants pay to them.

1. Orcs are strong, but they should not forget they are Orcs, not Humans. Humans are weak, but they are useful. Right now, orcs has lot of human vassals, and few kingdoms still struggling with us. Probably, we should stop struggling with them and wait, when humans overthrow knights and will invite our WarBosses to protect them? Its not impossible, it happened in few kingdoms we conquered before. But what if Orcs become interested in shiny trinkets, tasty food, leisure and indolence? We learn to be greedy and lazy. We become unfair. We will become the same as Barons, and humans will sooner or latter overthrow us, like they did it before with knights. So, let GodMother guide our Shamans to explain things to us properly, and provide us with WarBosses-of-WarBosses when we are in need of them. And let our humans be well fed, protected from outlaws and barons and be obedient and hard-working. Also orcs should never forget things Humans educated them - including reading and writing, building roads, wagons and ships, and, mainly, showing mercy and being fair. Orcs should never forget GodMother created both Humans and Orcs different. It was for reason, probably, to make both Humans and Orcs respect and help each other?

The points which struck me are:

• Orcs can eat almost anything.
• Orcs have little to no ranged weaponry.
• Orcs are superior in hand-to-hand combat.

To understand how you could make this work best to your advantage, you have to think about what would be a viable strategy against the orcs by the humans. You would probably only want to attack orcs at night when you have the surprise, as a fair fight in hand-to-hand combat would probably be a bad idea.

If you're faced with an attack by the orcs, you build walls. Ideally you return to your fortification / castle and wait them out. If they approach, you can bombard with arrows.

Now what would a genius orc tactician do to counter this? Play to your strengths. Have a fourth of your army stay awake at night and sleep during the day. Triple the number of guards guarding the encampment. Ensure that all your soldiers are within easy reach of a shield to guard against a ranged attack, even when they sleep.

When you attack the humans, you use their fortification / castle against them. The orcs perhaps may not like this bit as much but it is a very viable strategy: surround the castle. Stay out of bow range. Any food or goods from merchants entering the castle are prevented entry. The orc army pays for whatever food comes in as needed and sends them on their way (merchants still come, but now they're feeding your armies). ABSOLUTELY no merchants are to be harmed or mistreated, simply not allowed to enter the castle.

Use biological warfare. Assuming there are diseases which affect humans and not orcs, orcs can throw diseased animals into the castle.

Since orcs are superior at hand-to-hand combat, and the humans know this, you will need less to do the job, so you can put several castles under siege at once. And since orcs can eat almost anything, there will likely not be a shortage of supplies and the sieges can continue as long as they take.

Make it clear from the start that you demand their unconditional surrender and only the leaders will be killed. The people shall be let free. Keep your promises. Between the starving, the disease, and the promise to survive in case of surrender, they'll tear the leaders apart in short order and likely long before they'll starve to death.

If they do decide to fight, you ensure there are pikes in front and all soldiers have shields they can put above their heads. If resources are low, they can recycle shields from dead human soldiers.

• +1 it is worth adding that vastly more engagements in war were sieges than battles, and that in sieges the orcs' ability to eat almost anything gives them a massive advantage. Dec 20 '19 at 23:24

Economics based answer. The size of the army is a big factor. Only until recently human population was limited by food. And army can generally only be a percentage of population because the other population needs to produce food. If you say orcs can eat almost anything and they can eat plain grass and trees then their population is orders of magnitude less limited than humans. And the percentage how big can they build an army is also higher.

Suppose their limit of population is 1000 times higher per square km compared to humans and their army percentage is 50% of population compared to 10% of humans. So their army is 5000 times bigger per available square km. With these numbers they do not even need weapons or good strategy. The only thing they need is one person whom they follow and not fight between themselves.

The Mongols did not have a population advantage, but their army percentage was much higher than any agriculture country. Almost all of them could shoot the bow well enough. When Genghis Khan united the tribes, the Mongols conquered twice more land than the Roman Empire. They also had some technological advantage. But I think such big numbers of orcs can overcome any advantage in tactics and medieval technology.

This gives eleven contributing factors to Napoleon's success, and only two(ish) of them are actually about Napoleon himself. The main factors in the French Republic's military superiority came from the superior logistics, tactics, equipment and leadership they brought to the field. Yes you could credit the supreme leader with creating the culture that encouraged such innovation, but it's quite a subtle thing to bring to a society.

For an orcish culture like you describe, I think the biggest positive contribution he could make would be cohesion: introduce the sort of societal hierarchy that allows rank discipline, leadership, innovation for a higher purpose. As such, the warboss needs to be an awe-inspiring figure.

The warboss should not just be chosen by the shamans to be the leader of the tribe; they should be annointed as the fulfilment of the Ancient Prophesy of the 'Boss of Bosses', he who is come to bring the Orcs out of the darkness, etc etc etc (this pseudo-religious background could be entirely manufactured if you want this warboss to be particularly self-aggrandising). Support this religious fervour with lucky/well-executed initial military victories, and have it build on itself to form an actual cult, inspiring much greater discipline within the ranks than would normally be expected from a warband.

This would provide a mechanism for the warboss to solidify absolute control over his own warband without needing to be purely focused on internal shows of strength; indeed allows him to direct the warband to develop in areas (primary and secondary industry, logistics, cartography and surveying, etc) that would otherwise be scorned as 'for the weak', but which will provide greater long-term strength. It also allows the warband to exert control over other warbands by permitting a hierarchy where other warbosses can owe allegiance to a 'higher power' without compromising their own position of strength. Combined these would allow the Great Warboss to develop and stabilise a much larger and more focused army, which would have the capabilities to make previously-unheard-of strategic moves. Success in those moves would only strengthen the divine aura around the whole operation.

Napoleon level war boss should figure out how to make men fight at his side in form of thralls and occassional mercenaries or allies. Then use orcish forces with support of human artillery and cavalry.

In this case, orcish horde will be running out of forces much slower during their advance.

Now, how to do that, depends on too many factors.

Charge stoppers.

https://steamcommunity.com/sharedfiles/filedetails/?id=1858675654

Cavalry charges are devastating against massed infantry. Your world must find cavalry useful too since there are a lot of them. Supposedly disciplined infantry who present a massed front will not be charged; I am sure that is what you tell your infantry anyway. Pikemen won't be charged and that makes sense: the horses will hit pointy sticks. I understand that the guys with hammers at Agincourt had the hammers to drive pointy sticks into the ground and break up the expected cavalry charge; archers stakes.

https://en.wikipedia.org/wiki/Archer%27s_stake

Your orcs are like these Vlad units from Totally Accurate Battle Simulator. They carry great loglike stakes in their advance as anti cavalry weapons. The orcs are not so much well disciplined as confident. The stakes are sharp at both ends, because why not? If they are charged they put their stakes into the ground and prepare to receive the charge. If they engage with other foot units they can throw the stake when they get close or whirl it around like a claymore until they lose it, then switch to a mace.

If I were fighting orcs ike this I would mass the cavalry then fake a charge, peeling off before impact to reveal my cannons were lining up to deal with the orcs.

Pike and shot armies are designed to be able to defeat armies of knights or similar fighters. While men at arms need a lifetime of training and expensive equipment to function, pike and shot armies only need to drill volunteers or conscripts every week or so to be effective against knights.

The hedge of pikes provide protection against charges by cavalry or enemy infantry, while the ranks of arquebuses provides the means of dealing killing blows well beyond the range of hand held weapons. (Steel crossbows spanning 1200 lbs did the same thing prior to the large scale introduction of gunpowder).

Typical pike and shot army formation

Orcs seeking to charge in and carry out melee combat would be essentially the very sort of thing shot and pike armies were designed to counter, so unless the orcish armies are overwhelmingly large, or can strip vast areas of agricultural produce and production, then the humans actually hold the advantage.

The way to defeat a pike and shot army is to find ways to break their cohesion. Swiss pike formations were often attacked by German Landsknecht mercenaries using massive two handed swords to literally "cut through" the pike hedge, a very slow and dangerous job. The Spanish discovered the counter was to have swordsmen in the pike blocks to move out and counter any forces trying to slip into the pike hedge. Orcish armies seem well suited to using large swords, axes etc. to break the pike hedge, but may in turn fall prey to swordsman.

The Imperial army's defeat of pikemen employed by the King of France at the Battle of Pavia in 1525 decisively demonstrated the use of firearms as the means of defeating pike squares. The Imperial army utilized terrain, field fortifications and masses of cannon and arquebus fire to mow down the advancing Swiss mercenaries in their tightly packed pike squares.

Battle of Pavia. The Swiss, hemmed in by walls and slowed by broken terrain were unable to drive their attacks home against the Imperial artillery

While it seems unlikely the Orcish army has the leadership and resources the Imperial Army had, they may have success in breaking pike squares by throwing large rocks, heavy tree limbs and other objects into the pike square, or forcing battle on broken terrain where the pike squares have much more limited mobility. A full pike and shot army will still have their own firearms, but the slow rate of fire and the exposure to enemy cavalry (or orc) charges once the pike formations have been broken will provide the margin the orcs might need to win.

So the key to defeating pike and shot armies is to neutralize the protection of the pike squares, either by attacking them with swords and axes, forcing them to operate in broken terrain or literally smashing the squares with artillery or some equivalent.

However, human generals are generally quick learners, and expect changes in formations and tactics to counter these developments, much like armies continued to evolve through the 1600's.