Thanks to @capefoxalix for this art piece!
First appearance: 101 Thar Amphala
“Encounter” appearance: 102 Race to the Tower
Armor Class unknown
Speed unknown (flying speed)
Dex +3, Wis Save +3
+4 or greater to hit
Claw attack dealt 16 damage to Keyleth
Total health unknown, no damage taken
The gloomstalker, a Mercer creation and resident of the Shadowfell, is very similar to an undead cross between a dementor and a wyvern. These large creatures with 20-foot fleshless wingspans and elongated, snapping necks predatorily search from the skies for living flesh, using their fellow gloom stalkers to narrow their focus to the target they are hunting. Their skin billows in a black, shadow-like smoke, and gives off a freezing chill that reaches out to the very soul to those in close proximity.
Scanlan’s injured child Major Image was convincing enough that it distracted the gloom stalker from its intended quarry, Vox Machina. However, their bright, greenish-yellow eyes emanate cones of light that see through illusions. Illusions that fall under the cones’ influence disappear before the vision of others, as well. So, while the gloom stalkers aren’t terribly intelligent creatures, they’re not without their tricks.
It’s also Scanlan’s willingness to quickly use his 8th level spell, Dominate Monster, that saved Keyleth and Vox Machina from a protracted battle with the gloom stalkers. Though only one noticed Keyleth’s presence at first, several more were on their way to join in the hunt. Scanlan harnessed the power of the newly-named Mister Mistoffelees as an ambassador to the other gloom stalkers and as a flying steed, allowing Vox Machina a glimpse at what was happening on Entropis before the real battle began.