Sources
CR
Type
Size
Alignment
Movement

Geonid

Small Elemental, Neutral

Armor Class 17 (natural armor)
Hit Points 26 (4d6 + 12)
Speed 30 ft.
STR
12
+1
DEX
10
+0
CON
16
+3
INT
9
-1
WIS
14
+2
CHA
11
+0
Skills Perception +4, Stealth +2
Senses darkvision 60 ft., tremorsense 30 ft., passive Perception 14
Languages
Challenge 1/4 (50 XP)

Traits

Boulder Guise. While fully withdrawn into its shell, the geonid can't see and is indistinguishable from a small boulder

Actions

Club. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit:3 (1d4 + 1) bludgeoning damage.

Stone Tell. The geonid touches a stone object or surface and knows what types of creatures have been within 10 feet of that stone in the past 24 hours. The geonid can also determine the number of creatures of each type, but not their identities.

Lore

Also known as rocklings and rock hermits, geonids are small, intelligent cave dwellers that originated on the Elemental Plane of Earth. A geonid's arms and legs come out of a small opening in the bottom of its shell. A geonid can draw its limbs into its shell and close the opening. When it does so, the creature looks like a small boulder. In this state, the geonid can't see and relies on its tremorsense to detect other creatures nearby.