During an opponent's turn, activate Heart of Kiran by tapping Wylie Duke.
Wylie Duke triggers, causing you to draw a card and gain 1 life.
The Watcher's first ability triggers, creating a 1/1 Tentacle creature token.
Resolve the Heart of Kiran ability, causing it to become a creature until end of turn.
Activate Umbral Collar Zealot by sacrificing the Tentacle.
When the Tentacle dies, The Watcher's second ability triggers, untapping Wylie Duke and putting a stun counter on up to one permanent.
Resolve the Umbral Collar Zealot ability
Repeat.
This ingenious engine transforms a sluggish Leviathan into an active draw-and-sac machine by binding its fate to a curious loop of crew and sacrifice. With Arcane Adaptation naming Kraken, your Tentacle tokens step in to satisfy The Watcher in the Water's specific untap clause when they perish, while the Watcher itself slumbers away under its initial nine stun counters. Tapping Wylie Duke to pay for Heart of Kiran's crew cost simultaneously draws you a card on an opponent's turn and triggers the Watcher to spawn a Tentacle. You then feed that newly minted token to Umbral Collar Zealot, whose sacrifice triggers the Watcher to untap Wylie Duke so the whole breathtaking cycle can begin anew.