Anticausal Vestige + Cloudstone Curio + Sakashima's Student

Anticausal Vestige

Cloudstone Curio

Sakashima's Student

How it works

1. Cast Sakashima's Student by paying its mana cost. Choose to have it enter as a copy of Anticausal Vestige.
2. When Sakashima's Student enters, Cloudstone Curio triggers, returning Anticausal Vestige from the battlefield to your hand.
3. When Anticausal Vestige leaves the battlefield, it triggers, causing you to draw a card and and put Anticausal Vestige from your hand onto the battlefield.
4. When Anticausal Vestige enters, Cloudstone Curio triggers, returning Sakashima's Student from the battlefield to your hand.
5. When Sakashima's Student leaves the battlefield, it triggers, causing you to draw a card and put Sakashima's Student from your hand onto the battlefield as a copy of Anticausal Vestige.
6. Repeat from step 2.

This elegant looping mechanism relies on copying to create a self-sustaining cycle between Anticausal Vestige and Sakashima's Student. By casting Sakashima's Student to enter as a copy of Anticausal Vestige, you trigger Cloudstone Curio to bounce the original, which in turn causes Anticausal Vestige's leave-the-battlefield ability to replace itself and drop a permanent while drawing a card. You then alternate bouncing and re-entering the two creatures back and forth, turning Cloudstone Curio's passive type-matching trigger into an endless engine of draws and enter-the-battlefield effects.