Waterbend , : You may cast a noncreature spell from your hand without paying its mana cost. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for .)
Yue turns artifacts, tokens, and creatures into a free-cast engine: tap her plus enough permanents to meet the Waterbend cost, then jam your most expensive noncreature spell from hand for free each turn. You ramp into mana rocks and token producers, protect Yue, and use her to chain big counterspells, draw spells, and ultimately a game-ending payoff.
Repeatable free casting of any noncreature spell, including huge X-spells and expensive bombs
Flying and vigilance let her attack and still hold up Waterbend the same turn
Mono-blue gives deep access to counterspells, card draw, and protection
Synergizes with artifact ramp and token swarms that double as Waterbend fuel
Heavily commander-dependent—removal on Yue stalls the whole engine
Waterbend taps your board, leaving you exposed if it doesn't end the game
activation cost is steep without rocks or tokens to convoke it down
Mono-blue lacks efficient creature removal and struggles against fast aggro
A storm payoff that snowballs hard when cast for free off Waterbend.
Lower the curve of your Waterbend fuel with cheap mana rocks (Mana Crypt, Mana Vault, Mind Stone) and reliable token engines so you can activate Yue early and often. Add layered protection (Heroic Intervention's blue cousins, Counterspell, Swan Song, Mother of Runes effects via artifacts) to keep her alive. Then maximize impact with the format's best free-cast targets—Cyclonic Rift, Expropriate, Time Warp, and a tutor package to find them consistently.
Legendary Creature — Spirit Ally
each toward the cost.
, 
: You may cast a noncreature spell from your hand without paying its mana cost. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for