Sea Gate Stormcaller + Eternal Witness + Yavimaya, Cradle of Growth + High Tide + Snap

5-card combo · GU

Verdict

Yes — this 5-card loop generates infinite mana, infinite storm count, and infinite ETB triggers once Yavimaya, Cradle of Growth converts Islands into Forests to satisfy Eternal Witness's green requirement.

Cards required: 5
Cheapest stack total: $4.11
Color identity: GU
Popularity: 3 decks
Format: Commander

Buy required cards on TCGplayer

High Tide doubles Island output; Yavimaya, Cradle of Growth makes every Island a Forest Island so the green mana needed for Eternal Witness comes free from the same lands. Sea Gate Stormcaller copies Snap off its magecraft window, bouncing itself and Eternal Witness independently each cycle, which is what closes the loop and prevents either piece from staying in the graveyard.

Recipe

How it works

Prerequisites

You control at least two Islands.

Steps

Activate an Island by tapping it, adding .
Cast Sea Gate Stormcaller by paying .
Sea Gate Stormcaller enters the battlefield, causing you to copy the next instant or sorcery spell you cast this turn with mana value two or less.
Cast High Tide by paying .
Sea Gate Stormcaller triggers, copying High Tide.
Resolve both High Tides, adding an additional whenever you tap an Island for mana this turn.
Activate a Forest Island by tapping it, adding .
High Tide triggers twice, adding .
Cast Snap by paying , returning Sea Gate Stormcaller to your hand and untapping two Forest Islands you control.
Activate both Forest Islands by tapping them, adding .
High Tide triggers four times, adding .
Cast Sea Gate Stormcaller by paying .
Sea Gate Stormcaller enters the battlefield, causing you to copy the next instant or sorcery spell you cast this turn with mana value two or less.
Cast Eternal Witness by paying .
Eternal Witness enters the battlefield, returning Snap from your graveyard to your hand.
Cast Snap by paying , targeting Eternal Witness.
Sea Gate Stormcaller triggers, copying Snap, with the copy targeting Sea Gate Stormcaller.
Resolve the copy of Snap, returning Sea Gate Stormcaller to your hand and untapping two Forest Islands you control.
Activate both Forest Islands by tapping them, adding .
High Tide triggers four times, adding .
Resolve the original Snap, returning Eternal Witness to your hand and untapping two Forest Islands you control.
Repeat from step 12.

Result

Infinite ETB; Infinite LTB; Infinite magecraft triggers; Infinite mana lands you control can produce; Infinite storm count; Infinite untap of lands you control

Variations

Cheaper, tighter, alternate lines

The Yavimaya dependency is the combo's tightest constraint — without it, Eternal Witness can't be cast from the generated mana. In lists already running Breeding Pool or other blue-green duals, those lands satisfy the Forest Island requirement and make Yavimaya redundant; replace it with a fifth tutor. The loop produces infinite storm count but no built-in kill — Brain Freeze, Grapeshot, or a Blue Sun's Zenith-style sink finishes the table.