Armor design for fighting flying monsters?

Question

In my setting, there is a type of monster which is an aggressive, airborne humanoid which oftentimes preys on humans travelling through its habitat. Its prevalence, and the danger which it can cause has resulted in the warriors belonging to the area wearing armor designed with directly combatting attacks from these beings as a core purpose.

The creatures are large, gaunt winged humanoids, standing at 7 and a half feet, with a weight of roughly 90 kilograms. They are supernaturally strong, and easily capable of lifting a human from the ground. Their primary method of dispatching their prey is to grab them and rapidly ascend, before dropping them from a fatal distance (They are not dependent on this, however, and can reliably kill humans with their claws should they feel the need). They are less agile on the ground as humans, however, and thus prefer to attack from the air. They prefer hit and run tactics in groups of 4-8, slowly reducing a groups number through ambush, or wounding targets and letting them bleed, instead of direct confrontation, and will flee should they feel an engagement is against them, if only to regroup from a different direction, though they will retreat if they are aware they cannot win.

What are some ideas for armor designs which would effectively counteract these creatures? The faction possesses blacksmithing and leatherworking expertise similar to the Mongol Empire at its peak, has abundant reserves of horns/bone, hide, wood, and iron, and the climate is temperate enough to facilitate the long-term wearing of large, bulky armor. The armor design is for both infantry and cavalry.

My initial idea has been a suit of armor festooned with various long, barbed spikes made of iron and bone across the helmet, back and shoulders, so as to prevent easy grappling, and possibly maim the wings of the creatures should the wearer flail around enough. This would form the rationale for why suits of armor made for the nobility of the region are adorned with helmet horns and spiked pauldrons which would otherwise seem ludicrously unnecessary.

Answer 1

Spikey armor will just get tangled up on your spears, which have all the benefits of spikey armor, none of the drawbacks, an extra two or more meters of reach, and much better control and leverage, all for a much lower price. Should a man be grabbed, he can draw his short sword and again get all the benefits of spikey armor, an extra meter of reach, and much better control and leverage.

On top of being unnecessary and an impediment to using your better, longer, and stronger hand-held spikey things, spikey armor will just be such a pain that nobody will want to have it for longer than it takes to pose menacingly for a Frank Frazetta painting. It will keep poking holes in your cloak and pack, bothering your horse, getting stuck on the scenery, getting stuck on your friends' cloaks, packs, and horses, and generally being a bother to you and everyone around you.

Your guys' armor will look just like regular armor available to their civilization - which is to say, probably a metal or leather helmet with some basic neck protection and a few layers of sturdy cloth if you're a peasant or pastoral nomad, and chainmail if you're a professional man-at-arms. They'll prioritize the upper body even more than historical people did, and they won't like helmets that make it hard to look up.

I mean, if you want Frank Frazetta paintings, by all means have your warrior strap on his spikey shoulder pads, horned helmet, double headed battle axe, and loin cloth, douse himself and one or more mostly naked ladies in baby oil, and go do glorious battle with the Bat People. Nobody's going to tell you you can't. Well, some people will, but screw those fun-hating jerks. But you did ask specifically about effectiveness.