Rakdos Joins Up + Opalescence + Flesh Duplicate

Rakdos Joins Up

Opalescence

Flesh Duplicate

How it works

1. Cast Flesh Duplicate by paying its mana cost. Choose to have it enter the battlefield as a copy of Rakdos Joins Up.
2. Put Flesh Duplicate into your graveyard due to the legend rule.
3. Flesh Duplicate's first ability and second ability trigger, along with Rakdos Joins Up's second ability.
4. Resolve Flesh Duplicate's second trigger and Rakdos Joins Up's trigger, dealing damage to target opponent.
5. Resolve Flesh Duplicate's first trigger, returning it from your graveyard to the battlefield with two +1/+1 counters on it as a copy of Rakdos Joins Up.
6. Repeat from step 2.

This loop relies on the fascinating rules interaction between Opalescence, which turns enchantments like Rakdos Joins Up into creatures, and Flesh Duplicate, which can enter the battlefield as a copy of that newly minted enchantment-creature. Because Flesh Duplicate enters as a copy of Rakdos Joins Up while Opalescence is on the battlefield making both enchantments into creatures, the legend rule immediately forces one into the graveyard, triggering its own death ability—and thanks to Rakdos Joins Up's own enter-the-battlefield trigger combined with its legendary death watch, you can pull the clone right back out with extra counters to repeat the cycle infinitely and burn your opponent out of the game.