I play and have played a lot masterminds. I swear the pets have personalities.
My first villain on live, right after launch, was Necro/Poison. The third zombie was suicidal, he would run into combat face first while his brothers puked from a distance. The second grave knight was a coward. He refused to melee unless I /goto'd him. The lich just hated me.
My current Beasts/Nature mastermind's second howler wolf has separation anxiety. He stays right beside me until I tell him to attack, and returns as soon as that specific enemy is down, never joining the others in chewing on the next enemy.
My Mercs/Thermal's first Spec Ops is just a moron. "How do stairs work? You wanted me to go up to this guy and stare at him, right? etc."
Of course, I keep them on tight metaphorical leashes via numpad keybinds, but they still seem to have their quirks.