Enduring Scalelord, Undercover Operative, and Cathars' Crusade

Prerequisites

• Enduring Scalelord on the battlefield
• Undercover Operative in hand
• Cathars' Crusade on the battlefield
• available

Steps

1. Cast Undercover Operative by paying , choosing to have it enter the battlefield as a copy of Enduring Scalelord
2. Undercover Operative enters the battlefield, triggering Cathars' Crusade, putting a +1/+1 counter on each creature you control
3. Enduring Scalelord and Undercover Operative triggers
4. Resolve the Undercover Operative trigger, putting a +1/+1 counter on itself
5. Enduring Scalelord triggers, putting a +1/+1 counter on itself
6. Repeat from step 4

Results

• Infinite +1/+1 counters on Undercover Operative and Enduring Scalelord