Enduring Renewal + Workhorse + Vorinclex, Monstrous Raider

Enduring Renewal

Workhorse

Vorinclex, Monstrous Raider

How it works

1. Cast Workhorse by paying 6, causing it to enter the battlefield with eight +1/+1 counters on it due to Vorinclex, Monstrous Raider.
2. Activate Workhorse by removing a +1/+1 counter from it, adding C.
3. Repeat step 2 until Workhorse has no +1/+1 counters on it.
4. Workhorse dies as a state-based action due to having 0 toughness, triggering Enduring Renewal, returning Workhorse from your graveyard to your hand.
5. Repeat.

This elegant loop turns Workhorse into an infinite mana engine by manipulating its counters and recycling it through the graveyard. When you cast Workhorse, Vorinclex, Monstrous Raider doubles its usual entry counters to eight, giving you plenty of fuel to strip away for colorless mana. Once those counters are spent and the mechanical beast perishes from having zero toughness, Enduring Renewal steps in to immediately bounce it straight back to your hand for another round.