Posidriss
Quest reward from Hibernation. Posidriss is excited to go on adventures with you, but maybe let them have a nap first? Dragonkin type. Pet Abilities Source Notes / No abilities. Quest: Awarded during the Emerald Whelp part of the Whelp Daycare on Day 16.
The 
Posidriss is a non-combat battle pet obtained as a quest reward from the Emerald Whelp portion of the Whelp Daycare questline during Dragonflight, specifically awarded on Day 16 of the questline via the quest Hibernation.
Guide awaiting review
Progress the Whelp Daycare
Participate in the Emerald Whelp portion of the Whelp Daycare questline and reach Day 16 to receive Posidriss as a reward from the quest Hibernation.
Note Posidriss's size
Posidriss is notably much larger than a standard companion pet — roughly five times the size — so expect them to stand out prominently when summoned.
Tips
Posidriss uses they/them pronouns, which is reflected both throughout the Whelp Daycare questline and in their flavor text — a distinction unique among the whelps in the daycare.
Posidriss cannot participate in pet battles, as they have no combat abilities.
