For Toravon specifically, the orbs will bug fairly often, where one will not disappear after you have killed it, and no amount of [nodead] in your macros will fix it. It's just something that happens in that fight, and makes it a pain. Personally I just target them with the tank that is currently not tanking, and taunt it (they ARE tauntable) and have everyone assist that tank. You'll find this method to be easier anyway, as it gets the orb away from your team.