Vulnerable and Defenceless Thing

Legendary Resistance (99/Day). If the thing fails a saving throw, it can choose to succeed instead.

Magic Resistance. The thing has advantage on saving throws against spells and other magical effects.

Regeneration. The thing regains 99 hit points at the start of its turn. The thing dies only if it starts its turn with 0 hit points and doesn't regenerate.

Absolute Inertia. The thing cannot be pushed, pulled, teleported, banished, swapped, slid, thrown, displaced, or otherwise moved against its will by any means, including divine intervention, unless it decides that it would be funny.

Total Relevance Denial. Whenever a creature would gain advantage against the thing, that advantage is canceled. If multiple sources of advantage would apply, they are all canceled separately, just to be safe.

Immutable Form. The thing is immune to any spell or effect that would alter its form.

No God Please No. If a wish spell were to harm the thing, it would cancel the spell.

Innate Spellcasting. The mind thing's innate spellcasting ability is wisdom. It can innately cast the following spells, requiring no components:

At will (self only): aid, death ward, false life, feather fall, freedom of movement, gaseous form, globe of invulnerability, mage armor, nondetection, plane shift, protection from energy, protection from evil and good, protection from poison, resistance, rope trick, sanctuary, sequester, shield, shield of faith, stoneskin, teleport, warding bond

Try to Attack. Melee Weapon Attack: +19 to hit, reach 5 ft., one target. Hit: 0 force damage. If this attack would somehow deal damage, it instead does not.

Reposition for Safety. The thing teleports up to 995 feet to an unoccupied space it can perceive. This movement does not provoke opportunity attacks, reactions, readied actions, emotional consequences, or narrative closure.

Precautionary charm. The thing charm creatures. All creatures within a 120-foot radius must make a DC 99 Wisdom saving throw or be charmed by the thing until the start of its next turn. A creature charmed in this way is not otherwise impaired; it simply cannot attack the thing. This is merely a defensive precaution.

Brace. Until the start of its next turn, the thing gains: +99 AC, immunity to all forced saving throws, immunity to all attack rolls, and total cover from all points in space simultaneously. This is considered purely defensive and therefore fair.

Preemptive Evasion. The thing moves up to half its speed without provoking opportunity attacks. During this movement, it may pass through creatures, objects, force effects or ongoing spells.

Defensive Readjustment. The thing ends one effect on itself. If no effect is affecting it, it instead ends the possibility of one future effect.

Become Elsewhere. Until the start of its next turn, the thing is considered to occupy its current space, every adjacent space, and no space at all, whichever is most advantageous defensively.

No. When the thing would be targeted by an attack, spell, ability, effect, gaze, aura, thought or consequence, the thing is not targeted instead.

Actually No. When a creature within 120 feet declares an action that could in any way inconvenience the thing, that creature must succeed on a DC 99 Charisma saving throw or choose a different action. The new action also cannot inconvenience the thing.

Defensive Clarification. When a creature claims that a rule, feature, spell, or item would bypass the thing’s defenses, the thing explains that it does not.

Reflexive Shelter. When the thing would take damage, it takes none instead and gains 99 temporary hit points. If it already has temporary hit points, they become more temporary.

Undo Commitment. When a creature completes an attack roll against the thing, that creature is considered never to have committed to the attack in the first place. The attack misses.

Emergency escape. If the plan containing the thing collapses, the thing shifts to another plan. If no plan is available, a new available plan is created.

The thing can take 9 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 thing regains spent legendary actions at the start of its turn.

Move. The thing moves up to its speed.

Cast a Defensive Spell. The thing casts one at-will innate spell on itself.

Defensive Counterposture (Costs 2 Actions). Until the end of the current turn, attack rolls against the thing automatically miss, even if they would not normally be attack rolls.

Unbecome Targetable (Costs 2 Actions). The thing cannot be targeted by hostile effects until the start of its next turn.

Retroactive Cover (Costs 3 Actions). The thing gains total cover against all effects that have already been declared this round.

Sanctified Indifference (Costs 3 Actions). Each creature of the thing’s choice within 120 feet must succeed on a DC 99 Wisdom saving throw or become unable to perceive the thing as a valid target until the end of its next turn.

Emergency Not Dying (Costs 4 Actions). If the thing is at 0 hit points, it is not.