D&D 5E Anyone interested in my conversion of I3 for 5e?

[LabyrinthLord718]

Converted the first critter for I3. Would love any and all feedback. You will have to refer to the 1e Fiend Folio for the fluff and fighting tactics, though I plan on running the sandmen with a decidedly evil bent; they will attempt surprise in the desert, rising up from the sand beneath the party's feet and will attack any sleeping party member using their own weapons instead of leaving them sleeping with no further action.

*** SPOILER ALERT ***

SANDMAN
Medium humanoid (sandman), Neutral Evil

ARMOUR CLASS 14
HIT POINTS 50
SPEED 30 ft

STR 14 (+2)
DEX 16 (+3)
CON 10
INT 10
WIS 10
CHA 10

SKILLS Stealth (+2)
SENSES Passive Perception 12
LANGUAGES --
CHALLENGE 4 (1,100 XP)
DAMAGE IMMUNITIES Nonmagical missile weapons

AMBUSHER. The sandman has advantage on attack rolls against any creature it has surprised.
PERFECT CAMOUFLAGE. The sandman receives a +2 bonus when determining surprise.

ACTIONS
SLEEP AURA. Any character or monster coming with 20 feet of the sandman must make a CON save or fall asleep for 3 rounds. One save per round is permitted after 3 rounds. The sleeper awakens if violently disturbed.

SLEEP TOUCH. As Sleep Aura. Affects anyone touching or being touched by the sandman.

MELEE ATTACK. As weapon. +5 to hit, +2 damage.