You've had a Zombie enter the battlefield under your control this turn.
Mana Needed
({2} magic symbol) ({U} magic symbol) available.
Steps
Cast
Whim of Volrath with buyback by paying ({2} magic symbol) ({U} magic symbol) .
Geralf triggers, creating a 2/2 Zombie Rogue creature token.
When the Zombie Rogue enters the battlefield,
Geralf's second ability triggers, putting a +1/+1 counter on the Zombie Rogue for each other Zombie that entered the battlefield under your control this turn.
Resolve the
Whim of Volrath spell, returning it to your hand.
Activate the Zombie Rogue using Vivi's ability by paying ({0} magic symbol) , adding at least ({2} magic symbol) ({U} magic symbol) .
Repeat.
Results
Infinite ETB.
Infinite storm count.
Infinite red mana.
Infinite blue mana.
Infinite +1/+1 counters on an infinite number of creature tokens.