I don't really explore glitches much, though I do recall a time when I was playing Star Wars: The Old Republic (the mmo) pretty soon after its initial release and characters specifically as the Trooper class iirc had a bug that rendered them completely invincible if they were doing the dancing emote. This worked in pvp too. Needless to say that got fixed quickly, kinda sad because I started the game as a trooper vanguard, but it was funny nonetheless.