To begin with the gods of both Islam-esque and Christianity-esque in my story are just super humanoid beings with semi-immortality(They won't die but can be killed) but they already died including all their offsprings that would have taken their place. All thats left are their super advance technologies(The 'gods' were in fact the last 2 of their super advanced civilization).
Come 500 years after they died the religion that they established is still going strong with Crusades and Jihads dividing the world in half. The world has magic(a mutation from the god like humanoid beings)
The good thing about the crusades and jihad is that because the whole world is split in two and its might makes right rule in most areas, the roads are fully developed, there are industries capable of of supporting the armies of both sides on a massive scale. But also the population is always culled due to the crusades and jihad so suffering and poverty in most war torn places runs rampant but the inner territories of both sides flourishes due to its distance from war zone. The difference between the rich and poor is so large that the fear of rebellion can be realize once the crusades and jihad ends
Now you come to the story as someone from modern day earth and see the world divided in to two, just that this world is ripe of strife and suffering. Being the good person you are, you want to put a stop to it. The only probable way to do it is to create a religion to false gods. Upon stumbling on their hidden cache of technologies you are only able to use 3 things atm.
- Time Space storage device in form of watch
- Atomic re constructor device in form of a box which can be resized according to needs
- Orbital Microwave satellite cannon
Using these 3 technologies, you should achieve the following
- Stop the current crusade/jihad from advancing further
- Cull extremists from both sides
- Establish yourself as a prophet of a 'God of light' and establish a religion
- Destroy the validity of both Christian-esque and Islam-esque religions not with overwhelming military/fire power but influence and if possible economics
- Establish a pantheon of false(nonexistent) gods to denounce Christian-esque and Islam-esque further.
- Destroy all scriptures of the 2 religions
- Convert most(60%) of the population to your church, and you shall name it
"The Church of Violence"
you need to achieve all 7 before 50 years(Your probable time of death)
Your first course of action will be the total destruction of both crusading army and jihad army during a battle of massive proportions including all supplies, leaders and its support structure. This should buy you 1 to 5 years of free action anywhere in the continent to further your agenda and goals focusing mostly on the common and poor folk. From then onwards what would be the probable step to achieve the 7 objectives in 50 years time
The magic in this world are that what can normally be read on books or typical D&D game with more powerful magicians capable of destroying battalions of troops. Normally only magicians can beat magicians. 1 out of 50 people in this world are magicians. It is said that the magicians pulls of their magic from their belief, you on the other hand believe that it is not. YOu can expect little magicians joining your church however these magicians that you will breed will be a different kind one as you'll be able to teach them how does the world works.
Technology wise you can manufacture things that your are capable of thinking of, from simple clothing to flying ships(arks) of several kilometers long give if you have enough matter for the re constructor to use, with the atomic re constructor doing the hard work of production you should be able to at least shock and awe anyone you come across i mean you can raze cathedral down with your giant 'rod' of steel. Everything you produce you can store it on your time space watch. The hard part on the watch is that it doesn't tell time....
Not to mention your control over the orbital cannon is something that should be used wisely and strategically. It is not something you want to squander as you need to preserve the shock effect of firing it to your enemies. I mean you can turn a battlefield into a fiery wasteland in no time, any one survives that or sees that will be sure to be awed and scared of you and certainly will follow you ot of fear. YOu can even make nobles grovel down to you just to prevent you from firing at their territory. You destroying an army is enough to ensure of the compliance of any one who is able to see your deeds.
Also you must remember, you're the weakest human in that world. YOu dont have magic, you dont have the ability nor the capacity to survive in such landscape, you'll use your technology on hand to achieve the goals, but the paramount of all your goals require you to have the most powerful influence or at least someone of influence that is capable to swaying masses.
And also your church doesn't shy away from violence.