A couple of mine:
Foaming - Describes a temporary state an enemy is in when they’ve taken a bunch of damage and are now stronger, do more damage, etc.
Example sentence: Oh crap, now it’s foaming. Watch its projectile attacks, they do poison damage now.
Etymology: My brother and I made up this word in our Monster Hunter Freedom 2 days. The first time we noticed this phenomenon was when we were fighting a Daimyo Hermitaur (a giant crab like monster). When you damage it enough and it becomes more aggressive, white foamy bubbles come out of its mouth, hence the name.
Although technically only two of the monsters in that game “foam”, my brother and I applied the term to all the monsters in that game and even to enemies in other games (like the Flamelurker in Demon’s Souls for instance).
Anti-flinch Cream - A topical ointment one applies to oneself that prevents them from flinching when they take damage, prevents their attacks from being interrupted, etc.
Example sentence: I can’t stand Shao Khan in Mortal Kombat 9! Like 90% of his moves have anti-flinch cream!
Etymology: You essentially know this as an attack having “armor” properties. I can’t quite remember why I settled on this phrase, but I noticed in alot of fighting games, attacks with armor usually coat the user in a white sheen. I just think it’s kind of funny to imagine a character lathering themself in special lotion to avoid feeling pain from attacks