Sensei's Divining Top + Transplant Theorist + Ugin, the Ineffable

Sensei's Divining Top

Transplant Theorist

Ugin, the Ineffable

How it works

1. Cast Sensei's Divining Top by paying 0 due to Ugin, the Ineffable.
2. When Sensei's Divining Top enters, Transplant Theorist triggers.
3. Holding priority, activate Sensei's Divining Top by tapping it, causing you to draw a card and put Sensei's Divining Top on top of your library.
4. Resolve the Transplant Theorist trigger, causing you to draw Sensei's Divining Top from your library, and then discard a card other than Sensei's Divining Top.
5. Repeat

This ingenious loop turns a modest artifact into a self-sustaining engine by taking advantage of cost reduction and stack manipulation. With Ugin, the Ineffable blanking the mana cost of colorless spells, Sensei's Divining Top can be cast for free over and over. Every time it enters the battlefield, Transplant Theorist triggers to let you loot, but responding to that trigger by tapping Sensei's Divining Top to draw a card places the artifact neatly on top of your library just in time for the loot effect to draw it right back out.