Istvan, Butcher of Eln

Rulebreaker — If Tolabow, Loch Rascal is your commander, the color identity of instant and sorcery cards in your deck can include one color of your choice not in your commander's color identity, and your deck can have any basic land cards. Whenever you cast an instant or sorcery spell, create a 1/1 blue and red Otter creature token with prowess. (Whenever you cast a noncreature spell, it gets +1/+1 until end of turn.)

Whenever an artifact is put into a graveyard from the battlefield, put a number of +1/+1 counters equal to that artifact's mana value on Joven and Chandler. RRR, T: Gain control of target artifact until end of turn. Untap it. It gains haste until end of turn.