The Watcher in the Water + Wylie Duke, Atiin Hero + Heart of Kiran + Umbral Collar Zealot + Trickery Charm

How it works

During an opponent's turn, cast Trickery Charm by paying , causing Wylie Duke to become a Kraken.
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 from step 2.

In which brackets is this combo allowed, per Spellbook's Exhibition tier?

1–2 · Exhibition & Core

Allowed in this bracket.

3 · Upgraded

Allowed in this bracket.

4–5 · Optimized & cEDH

All combos are allowed.