WhiteDwarf: When you shove the SecOfficer into the locker, take his helmet. When the other SecOfficer throws the grenade, throw the helmet over it and hold it down with your foot

There we are. You can grab that, and then after that, you can do the cool backflip slash -- you can't do slashes while one hand is occupied like this. That's just the rules.

But when he throws that there, let's see...

Surely that's when that fool with the gun takes his shot.

Unless he's the one you -- retroactively -- slammed in the face with the baton you kicked earlier. The one you haven't kicked yet -- which is to say, the one you will have retroactively have kicked into his face. Smooth as clockwork, and every bit as logical. Okay, perfect, you're nearly done.

WhiteDwarf: Cut the SecOfficer's air tube again, the one made of flesh.