Arcanomech Reinforcement Drone

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

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

Shield Tether. The Arcanomech creates a magical shield around one arcanomech within 30 feet of it that isn't another reinforcement drone. The shielded creature gains a +5 bonus to their AC and saving throws. This shield ends if the tethered creature or the drone are more than 30 feet apart, if the tethered creature or the drone are behind total cover from one another, if the drone drops to 0 hit points, or if the drone ends the connection (free action).

Arcane Bolt. Ranged Weapon Attack: +5 to hit, range 60 ft., one target. Hit: 13 (3d6 + 3) force damage.