Yarus, Roar of the Old Gods + Master of the Veil + Bloodflow Connoisseur
Infinite +1/+1 counters on a creature, Infinite death triggers, Infinite ETB, Infinite LTB, Infinite sacrifice triggers
Activate Bloodflow Connoisseur by sacrificing Master of the Veil.
When Master of the Veil dies, Yarus' second ability triggers, returning Master of the Veil from your graveyard to the battlefield face down, then turning it face up.
Master of the Veil triggers, turning itself face down.
Resolve the Bloodflow Connoisseur ability, putting a +1/+1 counter on it.
Repeat.
Component Cards
How It Works
Activate Bloodflow Connoisseur by sacrificing Master of the Veil.
When Master of the Veil dies, Yarus' second ability triggers, returning Master of the Veil from your graveyard to the battlefield face down, then turning it face up.
Master of the Veil triggers, turning itself face down.
Resolve the Bloodflow Connoisseur ability, putting a +1/+1 counter on it.
Repeat.