Okay, so recently in my genocidal campaign against some giant ants, I accidentally tore a hole in reality and let some nether creatures in, including some Yuggs.
For some reason, Yugg Darts (which mutate you when they hit you) completely ignore armor. I’ve seen it multiple times, where I’ll be wearing Heavy Power Armor and still be hit by the Yugg Darts. I assume this is because the darts themselves don’t actually deal damage, and thus don’t check for armor.
I’m also going to point out that I don’t think it makes sense for a creature to potentially strengthen its target as a means of hunting. But that’s not the main focus of this.