Evolution Witness, and Hardened Academic

Prerequisites

• Evolution Witness on the battlefield
• Hardened Academic on the battlefield

Steps

1. Put a +1/+1 counter on Evolution Witness
2. Evolution Witness triggers, returning a permanent card from your graveyard to your hand
3. Hardened Academic triggers
4. Holding priority, activate Hardened Academic by discarding the permanent card
5. Resolve the Hardened Academic trigger, putting a +1/+1 counter on Evolution Witness
6. Repeat from step 2

Results

• Infinite +1/+1 counters on a creature
• Infinite self-discard triggers