Would it be a good idea to replace to sentinel beam's "bullet hole" decals with something like a glass decal (only on sand, dirt etc. materials)? It would make sense, since the sentinel beam's heat would melt the sand, dirt etc., turning it into glass. Also, would it be possible, or would it just suck and look bad? I checked some bullet hole decal tags, and saw that there weren't any slots for cubemaps, which is kinda dissapointing, but maybe some sort of cubemap could be baked into the texture?

Yeah, I thought about using a scenery object, but that would probably lag alot, because you'd be spawning more than 1 object per second, and if you'd be fighting like 4 sentinels, your pc probably won't handle it.

Could you add specular to the decal, or is that privelage reserved for BSP stuff?