Combine Guildmage, and Hammerhead, Maggia Boss

Prerequisites

• Combine Guildmage on the battlefield
• Hammerhead, Maggia Boss on the battlefield
• available

Steps

1. Activate Combine Guildmage's first ability by paying and tapping it, causing your creatures that enter this turn to enter with a +1/+1 counter on them
2. Activate Hammerhead by sacrificing the persist creature
3. When the persist creature dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it and at least one +1/+1 counter on it due to Combine Guildmage
4. Remove a -1/-1 counter and a +1/+1 counter from that creature as a state-based action
5. Resolve the Hammerhead ability
6. Repeat from step 2

Results

• Infinite +1/+1 counters on a creature
• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers