In honor of Kai Leng’s blades being coated with astatine in stasis and Shepard’s UF6 ODIN ammo block, I propose that Mordin to have dioxygen difluoride in his incendiary or hi-ex grenades. more info about this wonderful compund here and here . Perhaps discreetly gifted by his sister to him when he decided he’d open a clinic on Omega?
A substance that lights ice on fire. One of the things Mordin says in combat in the game comes to mind: “Flammable…or inflammable. Forget which, doesn’t matter!”