Cast Corpse Dance with buyback by tapping Caetus, Vampire Hexmage and two other creatures you control.
Displacer Kitten triggers, blinking Caetus and causing it to return to the battlefield as Invasion of Segovia.
When Invasion of Segovia enters the battlefield, it triggers, creating two 1/1 Kraken creature tokens.
Activate Vampire Hexmage by sacrificing it, removing all counters from Invasion of Segovia.
Invasion of Segovia triggers, causing you to exile it and cast it as Caetus, Sea Tyrant of Segovia.
Resolve Corpse Dance, returning Vampire Hexmage from your graveyard to the battlefield and returning Corpse Dance to your hand.
Repeat.
This clever loop harnesses the passive cost reduction of Helm of Awakening and the convoke-granting static ability of Invasion of Segovia's front face to cast Corpse Dance repeatedly with buyback. Each iteration is fueled by tapping your creatures—including the freshly returned Vampire Hexmage—to pay for the spell, which in turn triggers Displacer Kitten to blink your Siege. Blinking the Siege resets its status so that sacrificing Vampire Hexmage to remove its counters transforms it back into Caetus, Sea Tyrant of Segovia, generating fresh Kraken tokens and untapping your board to sustain the cycle indefinitely.