/vr/ - Retro Games

Here's the recolored gas.
I figured, since the enemies all die their bloody deaths anyway to it, it's probably something really horribly corrosive or a nervegas or something that burns and tears up your lungs and you just throw up lots of blood and gore and shit. The alt-fire even has a (relatively) slick loadup animation.

I don't know if maybe VX or Mustard Gas would do that (Mmm... mustard), but I figured a neon yellowish color would feel suitable for that visually. Let's also say it dissipates or solidifies against surfaces rather quickly or something, which is why you don't immediately die walking where it just was. And also your helmet has a decent filter. You'd probably have to sanitize a place where you blasted this shit though.