Elemental Mastery, Cathars' Crusade, and Cinderhaze Wretch

Prerequisites

• Elemental Mastery on the battlefield
• Cathars' Crusade on the battlefield
• Cinderhaze Wretch on the battlefield
• Elemental Mastery attached to Cinderhaze Wretch
• Cinderhaze Wretch does not have summoning sickness, and has a power of two or greater

Steps

1. Activate Cinderhaze Wretch by tapping it, creating at least two 1/1 Elemental creature tokens with haste
2. When the Elementals enters the battlefield, Cathars' Crusade trigger that many times, putting that many +1/+1 counters on each creature you control
3. Activate Cinderhaze Wretch by putting a -1/-1 counter on it, untapping it
4. Repeat

Results

• Infinite +1/+1 counters
• Infinite creature tokens with haste
• Infinite ETB