Oltec Matterweaver + Cavern Harpy + Kaya, Geist Hunter

Oltec Matterweaver

Cavern Harpy

Kaya, Geist Hunter

How it works

1. Activate Kaya's second loyalty ability by removing two loyalty counters from it, causing you to double all tokens you create this turn.
2. Cast Cavern Harpy by paying .
3. Oltec Matterweaver triggers, creating two token copies of any Treasure or Gold token you control.
4. When Cavern Harpy enters the battlefield, it triggers, returning itself from the battlefield to your hand.
5. Activate two Treasures by tapping and sacrificing them, or two Golds by sacrificing them, adding .
6. Repeat from step 2.

This elegant loop turns Kaya, Geist Hunter's replacement effect into an engine for infinite value, doubling every token generated along the way. As you cast Cavern Harpy, Oltec Matterweaver springs into action, leveraging Kaya's doubled-token clause to churn out multiple artifacts—like Gold or Treasure tokens—whenever a creature enters. You then use Cavern Harpy's own enters-the-battlefield trigger to bounce it right back to your hand for the cost of its mana, allowing you to sacrifice those newly minted tokens for the mana needed to cast it all over again.