Grove of the Burnwillows + Pili-Pala + Marvin, Murderous Mimic + Tainted Remedy + Sylvan Awakening

Grove of the Burnwillows

Pili-Pala

Marvin, Murderous Mimic

Tainted Remedy

Sylvan Awakening

How it works

1. Cast Sylvan Awakening by paying 2, causing all lands you control to become creatures until end of turn.
2. Activate Marvin using Grove of the Burnwillows' second ability by tapping it, adding or and causing each opponent to lose 1 life due to Tainted Remedy.
3. Activate Marvin using Pili-Pala's ability by paying 2 and untapping it, adding 1.
4. Repeat from step 2.