Closing in on world release, so here's a small update to the avatar weapons guide. Enemies are still hurt by colliding your particles with layer 29, but I've moved player health and armor to stereoleft and stereoright (15 & 16) to fix a physics layer bug that vrchat causes at runtime. If for some reason you want to pvp you should change those layers.

Again, collisions are limited to once per frame per particle system, so if you have shotgun or something on your avatar that does simultaneous collisions you'll want a separate particle system for each pellet.