Antimagic Susceptibility. The armor is incapacitated while in the area of an antimagic field. If targeted by dispel magic, the armor must succeed on a Constitution saving throw against the caster's spell save DC or fall unconscious for 1 minute.
False Appearance. While the armor remains motionless, it is indistinguishable from a normal suit of armor.
Actions
Multiattack. The armor makes two melee attacks.
Slam. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) bludgeoning damage.
RollQuest summary Condition immunities: blinded, charmed, deafened, exhaustion, frightened, paralyzed, petrified, poisoned. Senses: blindsight 60 ft. (blind beyond this radius), passive Perception 6. Languages: None. Speed: 25 ft.
RollQuest ships the D&D 2014 SRD as a content pack, on a 5e character sheet that does the maths - roll from the sheet and let the numbers work themselves out. Free to start.