Sensei's Divining Top + Starnheim Courser + Rook Turret

Sensei's Divining Top

Starnheim Courser

Rook Turret

How it works

1. Cast Sensei's Divining Top by paying 0 due to Starnheim Courser.
2. When Sensei's Divining Top enters, Rook Turret 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 Rook Turret 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 elegant engine relies on Starnheim Courser's cost-reduction ability to make Sensei's Divining Top entirely free to cast, bypassing the artifact's usual mana investment. Once the Top is on the battlefield, its tap ability lets you draw a card while tucking itself safely back onto the top of your library in response to Rook Turret's entry trigger. The Turret then lets you draw Sensei's Divining Top right back off your library and discard an unwanted card, looping seamlessly to fuel your graveyard, churn through your deck, and generate an endless stream of triggers.