Spawning Pit, and Zameck Guildmage

Prerequisites

• Spawning Pit on the battlefield
• Zameck Guildmage on the battlefield
• available

Steps

1. Activate Zameck Guildmage's first ability by paying , causing your creatures to enter with an additional +1/+1 counter this turn
2. Activate Spawning Pit 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 Zameck Guildmage
4. Remove a -1/-1 counter and a +1/+1 counter from that creature as a state-based action
5. Resolve the Spawning Pit ability
6. Repeat from step 2

Results

• Infinite charge counters on a permanent
• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers