4 cards where the text includes “flood counter” and the color identity ≤ U and (the card is available on Paper)

Aquitect's Will (Duel Decks: Merfolk vs. Goblins #2)
Eluge, the Shoreless Sea (Bloomburrow #49)
Quicksilver Fountain (Mirrodin #233)
The Flood of Mars (Doctor Who #45)

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