I'd actually remove the middle ability and give it Hexproof while untapped.
GAH I HATE BEHOLDERS SO MUCH. I'm not sure I understand why each ability was given the color it was, but that immediately betrays my lack of experience with the game.
Black frequently gets "Withering" effects. Blue counters spells in a "Dispel Magic" effect. Red usually gets the temporary mind control in a "Control Monster" vein.