Agatha's Soul Cauldron, Wildwood Mentor, Krark-Clan Ironworks, and Thopter Squadron

Prerequisites

• Agatha's Soul Cauldron on the battlefield
• Wildwood Mentor on the battlefield
• Krark-Clan Ironworks on the battlefield
• Thopter Squadron in exile
• Wildwood Mentor has at least one +1/+1 counter on it
• available

Steps

1. Activate Wildwood Mentor using Thopter Squadron's first ability by paying and removing a +1/+1 counter from it, creating a 1/1 Thopter artifact creature token
2. When the Thopter enters the battlefield, Wildwood Mentor's first ability triggers, putting a +1/+1 counter on itself
3. Activate Krark-Clan Ironworks by sacrificing the Thopter, adding
4. Repeat
5. Once you have infinite mana, you may forego sacrificing the Thopters
6. Once you have infinite creature tokens, you may activate Wildwood Mentor using Thopter Squadron's last ability any number of times

Results

• Infinite +1/+1 counters on Wildwood Mentor
• Infinite colorless mana
• Infinite creature tokens
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers