Sources
CR
Type
Size
Alignment
Movement

Thri-kreen Mystic

Medium Monstrosity, Any alignment

Armor Class 15 (natural armor)
Hit Points 99 (18d8 + 18)
Speed 30 ft.
STR
12
+1
DEX
15
+2
CON
13
+1
INT
12
+1
WIS
16
+3
CHA
10
+0
Skills Perception +6, Stealth +5, Survival +6
Senses darkvision 60 ft., passive Perception 16
Languages telepathy 60 ft., Thri-kreen
Challenge 5 (1,800 XP)

Spellcasting

Spellcasting (Psionics). The thri-kreen casts one of the following spells, requiring no spell components and using Wisdom as the spellcasting ability:

At will: levitate (self only), mage hand (the hand is invisible)

1/day each: freedom of movement (self only), invisibility (self only)

Actions

Multiattack. The thri-kreen makes two Gythka attacks or four Psychic Bolt attacks.

Gythka. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit:10 (2d8 + 1) slashing damage.

Psychic Bolt. Ranged Spell Attack: +6 to hit, range 60 ft., one creature. Hit:6 (1d6 + 3) psychic damage.

Drain Vitality (Recharges after a Short or Long Rest). The thri-kreen targets one creature it can see within 30 feet of itself. The target must make a DC 14 Constitution saving throw, taking 32 (5d12) necrotic damage on a failed save, or half as much damage on a successful one. The thri-kreen regains hit points equal to the damage dealt.

Bonus Actions

Chameleon Carapace. The thri-kreen changes the color of its carapace to match the color and texture of its surroundings, gaining advantage on Dexterity (Stealth) checks it makes to hide in those surroundings.

Lore

Thri-kreen mystics use psionics to navigate difficult terrain in Wildspace, turn invisible, and drain life from their prey. They often serve as spelljammers aboard thri-kreen ships.