Malcolm, Keen-Eyed Navigator + Magmaw + Runed Stalactite + Kaya, Geist Hunter

Malcolm, Keen-Eyed Navigator

Magmaw

Runed Stalactite

Kaya, Geist Hunter

How it works

1. Activate Kaya's second loyalty ability by removing two loyalty counters from it, causing you to double any tokens you create this turn.
2. Activate Magmaw by paying 1 and sacrificing another nonland permanent, dealing 1 damage to an opponent.
3. Malcolm triggers, creating two Treasure tokens.
4. Activate a Treasure by tapping and sacrificing it, adding 1.
5. Repeat from step 2

This clever loop turns Magmaw into a lethal engine by giving it a steady stream of ammunition, thanks to Runed Stalactite transforming it into a Pirate that triggers Malcolm, Keen-Eyed Navigator whenever it deals damage. Kaya, Geist Hunter pulls double duty here, using her minus ability to double every Treasure token created so that sacrificing them leaves you with a net profit of mana and disposable permanents. By continuously spending that mana to let Magmaw hurl damage directly at your opponents while recycling Treasures through the loop, you convert that token multiplier into an endless cycle of destruction.