Everyone probably knows that guy standing guard outside Rabanastre. The guy called 'Rabanastre Watch'. He's a Bangaa and he sometimes cure/protects the party. Well, I targeted him with Death (using R1 since he's not a enemy) and killed him! I thought he'd be immune but the next second he was falling on his face, dead! I wonder if you could Steal from him... if he comes back, that is.
Also, another funny thing is Cannibalize, especially when a monster such as Preying Mantis eats another Preying Mantis.
I watched two monsters (one huge dragon thing and a small gorgimera) having a duel in the Zertinan Caverns. Obviously, the dragon was winning.
I wonder why monsters fight like that...?
In Barheim Passage, a single confused frog hit itself. It's funny watching anything confused attack itself (and sometimes block it, like Penelo did while confused, she kept blocking her own attacks...).