Animated Statue - Marilith

 
This automaton resembles the demon Marilith, a tall female figure, with a snake-like lower body and six arms wielding swords.

Armor Class 15 (natural armor)                              Hit Points 90 (10d12 + 20)

Speed 40 ft.
STR          DEX          CON         INT          WIS         CHA
18 (+4)    18 (+4)    20 (+5)    14 (+2)    10 (+0)    14 (+2)
 
Skills: Perception +6     
Senses: darkvision 60 ft., passive Perception 16
 
Damage Resistances fire, cold.
Damage Immunities poison, disease.
 
Multiattack. The statue makes as many attacks as it has arms.

Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 8 (1d10 + 3) piercing damage.

Challenge 6 (3,500 XP)

If and when defeated, the statue will be revealed as made of cleverly-constructed canvas and wood.