|“||If you ask me, this place is even more dangerous than the Ares' Cabin. At least with Ares, you can learn where the land mines are.||”|
–Annabeth comparing Hypnos' cabin to Ares' Cabin, The Lost Hero
The cabin is made of mud walls and a rush roof. A wreath of red poppies hangs on the door. Inside, there's a hearth with a crackling fire. Above the mantel hangs Hypnos' symbol: a poplar tree branch dripping water from the river Lethe, into a collection of tin bowls. Soft violin music is always playing, and the air always smells like fresh laundry. The smell of Clovis's breath indicates there's warm milk in the cabin. There are always plenty of empty beds, all with feather pillows, fresh sheets and fluffy quilts. The Hypnos cabin makes everyone feel like sleeping, with its cozy and comfortable feel. Jason Grace almost buckled on his knees and fell asleep, but Annabeth Chase "snapped him out of it" and she described the cabin as being more dangerous than Ares' Cabin.
- Two unnamed others
- They are capable of memory retrieval.
- They are capable of memory alteration.
- They can induce sleep.
- They can use hypnosis.
- They can astral project/dream travel. (when asleep)
- They can manipulate dreams.