Aristeia, the Plauged Iron Maiden

Immutable Form. The Plauged Iron Maiden is immune to any spells that might alter its form.

Elemental Resistance. The Plauged Iron Maiden has advantage on saving throws against spells that utilize elemental abilities, such as fire,frost,or lightning. 

Armored/Exposed State. The Plauged Iron Maiden has the ability to "transform" at will, either revealing the fleshy monster underneath in its Exposed state or retreating back into its shell in its Armored state.

Exposed State - Large Eye. When the Plauged Iron Maiden is in its Exposed state, a single large eye is vulnerable. This weak point will deal critical damage if hit. Roll a d100 to determine accuracy when aiming for the eye with a ranged weapon. Any roll above an 80 will count as a critical hit. Attackers may add their Dexterity modifier to this accuracy roll. 

State-Dependent Multiattack. The Plauged Iron Maiden can make a total of two attacks per turn. It can only make certain attacks based on the state it is currently in (cannot do an Exposed and Armored attack each unless the Shift States reaction is activated).

(Armored) Chain Whip. Ranged Weapon Attack: +13 to hit, reach 15 ft. cone, multiple targets. Hit: 14 (3d6) slashing damage. 

(Armored) Door Slam. Melee Weapon Attack: +18 to hit, reach 5 ft., one target. Hit: 10 (1d8+4) bludgeoning damage.

(Exposed) Slam. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 14 (2d6+4) bludgeoning damage.

(Exposed) Bite. Melee Weapon Attack: +9 to hit, reach 8 ft., one target. Hit: 8 (1d6+4) piercing damage plus 4 (1d4+2) acid damage.

(Exposed) Acid Spit. Ranged Weapon Attack. The Plauged Iron Maiden spits a concentrated jet of acid at one target. The target must succeed at a DC 18 Dexterity saving throw, taking 16 (2d8+2) acid damage on a failed save, or half as much damage on a successful one. 

Absorb Flesh. The Plauged Iron Maiden gains its strength by consuming any carrion it can find. When it is within 10 feet of a small, medium, or large body that has been deceased for less than half a day, the mutant will extend a fleshy pseudopod from within its armor to collect the body. When assimilated, the Plauged Iron Maiden regains 1d6 of its health if damaged. 

Activate Reaction. The Plauged Iron Maiden may use its Bonus Action to use of its Reactions instead. 

Shift States. When damage is dealt towards it, the Plauged Iron Maiden can revert to whichever state it wasn't already in if it chooses. 

Armored State - Protracting Spikes (once per two turns). While in the Armored State, the Plauged Iron Maiden can further protect its body with spikes that protract from its iron shell. For its next attack, an additional 1d6 is added for piercing damage if it performs any melee attacks in the Armored State. After this attack, the spikes retract and cannot be activated again until two turns pass. 

Crushing Charge (Costs 1 Action). The Plauged Iron Maiden moves up to its movement speed in a straight line. During this move, it can enter the space of a Large or smaller creature's space. A creature whose space the construct enters must make a DC 18 Dexterity saving throw. On a successful save, the creature dodges out of the path of the charging iron maiden. On a failed save, the creature falls prone and takes 22 (4d6+4) bludgeoning damage. After the Plauged Iron Maiden makes its charge, it must turn around and face its adversaries. 

Horrifying Presence (Costs 1 Action). Each creature within a 40 foot radius of the construct's choice and is aware of the construct must succeed a DC 14 Wisdom saving throw or the creature(s) will be frightened for the next 3 turns. The frightened creature may attempt the saving throw again at the end of their turn, ending the effect on a success. Any successful result will allow the creature to be immune to Horrifying Presence for the next 24 hours. 

Cage of Torment (Costs 2 Actions). The Plauged Iron Maiden can attempt to grapple any Large or smaller creature within 10 feet of it. The creature must make a DC 16 Dexterity saving throw. On a successful save, the creature evades the grapple attempt. On a failed save, the construct grapples the creature and automatically shifts into its Armored state. It places the creature within the holding area of the iron maiden itself, and the creature takes 14 (2d6+6) piercing damage plus 6 (1d4+2) acid damage for every turn they are trapped within. The creature may escape from the Plauged Iron Maiden by any of the following: 

• The construct reverts into its Exposed state
• The construct is Stunned
• The creature succeeds on a D18 Strength saving throw
• The creature loses all health and is knocked unconscious

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