Marilith

The marilith makes seven attacks: six with its longswords and one with its tail.

The marilith makes six Pact Blade attacks and uses Constrict.

The marilith adds 5 to its AC against one melee attack that would hit it. To do so, the marilith must see the attacker and be wielding a melee weapon.

Trigger: The marilith is hit by a melee attack roll while holding a weapon. Response: The marilith adds 5 to its AC against that attack, possibly causing it to miss.

The marilith has advantage on saving throws against spells and other magical effects.

The marilith has Advantage on saving throws against spells and other magical effects.

The marilith can take one reaction on every turn in a combat.

The marilith can take one Reaction on every turn of combat.