Katara, Bending Prodigy + Ashnod's Altar + Nadir Kraken + Zirda, the Dawnwaker + Bard, King of Dale

Katara, Bending Prodigy

Ashnod's Altar

Nadir Kraken

Zirda, the Dawnwaker

Bard, King of Dale

How it works

1. Activate Katara by paying 4 due to Zirda, causing you to draw a card.
2. Nadir Kraken triggers, causing you to pay 1 to put a +1/+1 counter on it and create two creature tokens.
3. Activate Katara by paying at most 2 and tapping the creature tokens.
4. Holding priority, activate Ashnod's Altar twice by sacrificing the creature tokens, adding CCCC.
5. Resolve the Katara ability, causing you to draw a card.
6. Repeat from step 2.

This ingenious loop harnesses Zirda, the Dawnwaker to slash Katara, Bending Prodigy's waterbend cost down to a manageable four mana, turning every activation into a fresh card. That drawn card immediately feeds Nadir Kraken, whose trigger invites you to pay a single mana to grow larger and spin out a Tentacle token. Bard, King of Dale enters the fold to supercharge those tokens, doubling the creation into a pair of sacrificial offerings. You can then tap those very tokens to help pay for Katara's next waterbend activation before feeding them to Ashnod's Altar for a surplus of colorless mana, fueling the engine indefinitely.