Emry, Lurker of the Loch + Displacer Kitten + Lotus Petal + Breaching Hippocamp

Emry, Lurker of the Loch

Displacer Kitten

Lotus Petal

Breaching Hippocamp

How it works

1. Activate Emry by tapping it, targeting Lotus Petal.
2. Cast Lotus Petal from your graveyard by paying 0.
3. Displacer Kitten triggers, blinking Breaching Hippocamp.
4. When Breaching Hippocamp enters, it triggers, untapping Emry.
5. Activate Lotus Petal by tapping and sacrificing it.
6. Repeat.

This elegant loop relies on Emry, Lurker of the Loch to continuously pull Lotus Petal from your graveyard, fueled by the mana that same Petal provides upon sacrifice. The real engine, however, is Displacer Kitten: every time you cast that Lotus Petal, the Kitten triggers to blink Breaching Hippocamp. When the Hippocamp re-enters the battlefield, its ability untaps Emry, resetting the merfolk for the next iteration.