Harald Unites the Elves, Moritte of the Frost, and Phantatog

Prerequisites

• Harald Unites the Elves in hand
• Moritte of the Frost in the graveyard
• Phantatog on the battlefield
• available

Steps

1. Cast Harald Unties the Elves by paying , causing it to enter the battlefield with a lore counter on it
2. Harald Unites the Elves' first chapter ability triggers, causing you to mill three cards, and return Moritte from your graveyard to the battlefield as a copy of Harald Unites the Elves with one lore counter on it
3. Moritte of the Frost's first chapter ability triggers, holding priority, activate Phantatog's first ability by sacrificing Moritte of the Frost, giving it +1/+1 until end of turn
4. Resolve the Moritte of the Frost trigger, causing you to mill three cards, and return Moritte from your graveyard to the battlefield as a copy of Harald Unites the Elves with one lore counter on it
5. Repeat from step 3

Results

• Infinitely large Phantatog until end of turn
• Infinite self-mill