Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight, Megatog, and Clockwork Hydra

Prerequisites

• Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight on the battlefield
• Megatog on the battlefield
• Clockwork Hydra on the battlefield

Steps

1. Activate Megatog by sacrificing Clockwork Hydra
2. When Clockwork Hydra dies, its persist ability triggers, returning it from your graveyard to the battlefield without a -1/-1 counter on it due to its replacement effect
3. Resolve the Megatog ability
4. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers
• Infinitely large creature until end of turn