Brass Shinryu

Angel's Sight. Magical darkness doesn't impede The Shinryu's darkvision. 

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

Angelic Weapons. The Shinryu's weapon attacks are magical. 

Reckless. At the start of my turn, the Shinryu can gain advantage on all melee weapon attack rolls during that turn, but attack rolls against it have advantage until the start of its next turn.

Change Shape. The humanoid magically polymorphs into a shining, brass dragonoid that is a size large or back into its true form. It reverts to its true form if it dies. The Shinryu chooses whether its equipment falls to the ground in its space, merges into your new form, or is worn by it. Worn equipment functions as normal, but the DM decides whether it is practical for the new form to wear a piece of equipment, based on the creature’s shape and size. Its equipment doesn’t change size or shape to match the new form, and any equipment that the new form can’t wear must either fall to the ground or merge with it. Equipment that merges with the form has no effect until the Shinryu leaves the form.

Multiattack. The Shinryu makes two attacks: one with its mace and one with its claw.

Righteous Reprisal. In response to taking damage, the Shinryu makes a bite attack against the creature that damaged the Shinryu if it is within 5ft of the Shinryu. If the creature is not within reach, the Shinryu moves up to half its speed toward the creature, without provoking opportunity attacks.