During the final, boss wave of Aquanos, the Kraken will spawn near the northwest corner of the map. The Kraken has multiple tentacles projecting out the back of its body. The Kraken itself will remain invulnerable until all of its tentacles have been destroyed by player attacks. Hero defenses cannot target the tentacles. Any damage dealt to the tentacles appears in purple text above the Kraken's head. When its tentacles are destroyed, the head becomes vulnerable to attacks from both heroes and defenses. Once the Kraken loses 20% of its health, it will immediately regenerate its tentacles and regain invulnerability. Therefore, players must destroy the tentacles five times to defeat the boss.
The Kraken will fire blasts of water at heroes from a distance. It can also whip its tentacles at heroes coming within melee range, significantly knocking them back. The Kraken may fire homing spines from each of its tentacles, dealing significant damage. Once all tentacles are destroyed the Kraken will emit a damaging gas.
As the fight progresses, the map will gradually fill up with water limiting attack speed and movement. Similar to other boss fights, monsters will spawn endlessly while heroes attempt to defeat the Kraken.
Defeating the Kraken will unlock the Yellow Eternia Shard.
A Squire, Countess or Jester with a 100%+ block weapon can tank the Kraken and take minimal damage. Only the gas attack hits through the guard. This is particularly effective if paired with Mage Minions. Unlike other defenses, minions can target the Kraken, as the damage is useful in destroying the tentacles and will not aggro the Kraken. A Strength Drain and Healing aura combination will allow the tank to ignore having to sporadically heal, but they are not required.