Kenrith, the Returned King + Crystalline Crawler + Heartstone + Doc Samson, Super Psychiatrist
Kenrith, the Returned King
Crystalline Crawler
Heartstone
Doc Samson, Super Psychiatrist
Infinite +1/+1 counters on creatures you controlInfinite card draw for any number of playersInfinite colored manaInfinite draw triggers for any number of opponentsInfinite lifegainInfinite lifegain triggersReturn all creature cards from all graveyards to the battlefield under your control
How it works
Activate Kenrith by paying , putting two +1/+1 counters on Crystalline Crawler.
Activate Crystalline Crawler by removing a +1/+1 counter from it, adding .
Repeat.
This loop relies on an extraordinary synergy of counters and cost reduction to spin completely out of control. With Heartstone on the board making creature abilities cheaper, Kenrith, the Returned King can pump Crystalline Crawler for just {G} instead of {{1}{G}}. Meanwhile, Doc Samson, Super Psychiatrist turns that single counter placement into two, meaning every activation puts more counters on Crystalline Crawler than you spend to remove them. You simply remove a counter from Crystalline Crawler for mana to fuel Kenrith, the Returned King, netting an ever-growing surplus of mana and infinite +1/+1 counters in the process.