Female Titan (5e Creature)
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Gargantuan aberration, neutral evil
Transformation. A Titanshifter can transform into a Titan, in this case, the Female Titan. When the Titanshifter in human (or humanoid) form has a purpose in her heart and damages themselves, she shifts into a Titan. The Titan forms out of air and manifests in seconds. The shifter's Intelligence, Wisdom, and Charisma scores stay the same (the ones in the stat block are from the Annie, the shifter from Attack on Titan). Once the Titanshifter wants to revert back to humanoid form, she will pop out of the Titan's nape, and the body will slowly melt into steam.
Curse of Ymir. 13 years after its first transformation, the Titanshifter will die. Only a wish spell can prevent this from happening.
Siege Monster. The Female titan deals double damage to objects and structures.
Regeneration. The Female Titan recovers 20 hit points at the start of each of its turns. The humanoid inside it also regenerates half of these hit points. If the Female Titan takes any form of damage to the nape of its neck, this trait doesn't function at the end the Female Titan's next turn. The Female Titan only dies if the humanoid inside it dies.
Weak Point. The nape of the Female Titan's neck is a weak point. An attack which specifically targets the Attack Titan's nape deals damage to the person inside (usually a commoner unless otherwise specified by the DM). If the person inside dies, the Titan dies instantly. You must climb up the Female Titan to the nape with a Melee attack, or you can try to shoot it with a ranged weapon at disadvantage.
Action Name. Melee Weapon Attack: +X to hit, reach 5 ft., one target. Hit: X (1dX + X) damtype damage.
The can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The regains spent legendary actions at the start of its turn.