Sensei's Divining Top + Herald of Kozilek + Experimental Frenzy

Sensei's Divining Top

Herald of Kozilek

Experimental Frenzy

How it works

1. 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.
2. Cast Sensei's Divining Top from the top of your library by paying 0.
3. Repeat

This clever loop turns your library's top card into a self-sustaining engine by marrying Experimental Frenzy's top-of-library casting permission with the clever repositioning of Sensei's Divining Top. Normally, casting the Top from the top of your library would cost its standard mana value, but Herald of Kozilek steps in as a vital cost reducer that makes colorless spells cost {1} less, dropping the Top's casting cost completely down to zero. You simply tap Sensei's Divining Top to draw a card and place it back on top of your library, cast it immediately for free using Experimental Frenzy, and repeat the process endlessly to cycle through your entire deck.