Infinite card drawInfinite draw triggersNear-infinite creature tokensNear-infinite untap of creatures you controlNear-infinite mana creatures you control can produceInfinite mana lands you control can produce
How it works
Activate Karn by paying 1, causing Halo Fountain to become a creature.
Activate Incubation Druid by tapping it, adding
Activate Halo Fountain's second ability by paying , tapping it, and then untapping it and Incubation Druid, causing you to draw a card.