DM's Workshop: The Stone Dryad

Here is a very rough first pass at writing up the spotlight creature from upcoming adventure module TC2 in 5th edition format.

Very much a work in progress, like most (ok... ALL) of the TC series.

Stone Dryad

Medium elemental, neutral evil

Armor Class 15 (natural armor)

Hit Points 75 (10d8 + 30)

Speed 35 ft. fly 50 ft.

 STR DEX    CON      INT      WIS    CHA

14(+2)   12(+1) 16(+3)  11(+0)   10(+0)   16(+3)

Damage Resistances bludgeoning, piercing, and slashing from nonmagical weapons that aren't adamantine

Damage Immunities poison
Condition Immunities exhaustion, petrified, poisoned 

Senses darkvision 60ft., passive Perception 10

Languages Common, Terran
Challenge 5 (1800 XP)

False Appearance While the stone dryad is motionless, it is indistinguishable from an inanimate statue.

Petrifying venom If a creature loses more than half its hit points to the stone dryad’s bite attacks, it must make a DC 14 Constitution saving throw. If the saving throw fails by 5 or more, the creature is instantly petrified. Otherwise, a creature that fails the save begins to turn to stone and is restrained. The restrained creature must repeat the saving throw at the end of its next turn, becoming petrified on a failure or ending the effect on a success. The petrification lasts until the creature is freed by the greater restoration spell or other magic.

Actions

Multiattack. A stone dryad attacks with its claws and a bite.

Bite. Melee Weapon Attack: +5 to hit, reach 5ft., one target.

Hit: 9 (2d6 + 2) piercing damage, plus petrification (see above)

Claws. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. 

Hit: 9 (2d6 + 2) slashing damage.

Stone Maiden’s Curse: Those bitten by a stone dryad who escape immediate petrification are not safe. After six hours, the victim will begin to suffer from fever, aching joints, and chills, gaining a level of exhaustion, and only regain half the normal amount of hit points from a short or long rest. After each long rest, the creature must make a DC 15 Constitution saving throw. On a success, their condition improves, and they lose a level of exhaustion. On a failure, they gain another level of exhaustion, and further saving throw DCs increase (cumulatively) by one. If the creature should perish from extreme exhaustion, they turn to stone. If the creature is a humanoid male, the statue awakens on the next full moon as a gargoyle. If the creature is a humanoid female, it awakens as a stone dryad.