The wording is the same as Warrior Skill. So would this cause attacks with multiple instances to have each instance increased? Something like Melee can only target the enemy once (so 4 damage to a confused enemy and 3 damage to another). Buy Gambit's Royal Flush could hit the same enemy three times ans each instance would get plus one, right?

I think this card has a lot of value in multiplayer where one player can confuse and then other players can just pile on the damage. In solo, you can get more out of it by staying in hero mode.