From Halopedia, the Halo wiki

"My wife raised merses in our garden shallows. Never liked them much myself."
The Didact to Bornstellar Makes Eternal Lasting.

Merse are a species of carnivorous aquatic creature.


They resembled fleshy lily pads ringed with long black teeth, floating beneath the surface of the water and rooted to the lakebed by thick stalks. They are highly territorial towards intruders in their waters.[1]

Merse were sensitive to electromagnetic fields, and responded violently when a strong source of them (such as a Forerunner suited in armor) approached.[2][3] They were also irritated by excess noise and rough weather.[4] They communicated by "singing" to one another, and by using instruments to replicate their songs, one could sail through them safely. Merse reproduced asexually, and their songs changed in tone and composition with each generation.[1] However, the new generations rarely invented new songs, and instead often recycled older ones in a cyclic fashion.[4]


Their home planet was unknown, but a population of merse were transplanted into Djamonkin Crater on Earth to guard the Didact's Cryptum. Additionally, the Librarian raised merse in the garden of her and the Didact's domicile.[3]

On Installation 07, Chakas, Gamelpar and Vinnevra encountered what Chakas thought was merse on a great salty ocean until he saw its fin.[5]

When the Librarian created Bastion in the image of Earth, she recreated Djamonkin Crater and filled it with merse, just like the real crater on Earth.[6]

List of appearances[edit]


  1. ^ a b Halo: Cryptum, page 11-12
  2. ^ Halo: Cryptum, page 13
  3. ^ a b Halo: Cryptum, page 83
  4. ^ a b Halo: Cryptum, page 19
  5. ^ Halo: Primordium, page 158
  6. ^ Halo: Point of Light, Epilogue