Abomination

The Abomination is a large Flood form encountered on the Ark in 2559. It was first introduced in Halo Wars 2's Awakening the Nightmare expansion, which also introduced the Flood as an enemy.

Description
The Abomination is a massive Flood forms, towering above combat forms and brutes and appears to be even larger than certain vehicles utilized by the Banished. Its main torso appears to be covered in large glowing buldges while the rest of its body is a uniform colour. An Abomination has two arms, one ending in a single long tentacle, while the other has several, thinner tentacles, both of which are used as whips against its enemies.

Trivia

 * The Abomination appears to be based on the Flood Juggernaut, a Flood form that was cut from Halo 2.