Clockwork Pinwheel Dancer

Immutable Form: The construct is immune to any magic or effect that would alter it's form.

Magic Resistance: Has advantage on saving throws against spells and other magic effects. 

Ball Casters: The spheres that allow movement of the construct adjust to compensate for changes in terrain. The construct ignores difficult terrain except those created by magic or magical effect.

Multiattack: Can use up to 3 different ranged weapon attacks unless one or more of the rings is disabled

Top Ring Dart (Cold): Ranged Weapon Attack: +8 to hit, range 60/240 ft., 1 target. Hit: 10 (1d10 + 4) cold damage.

Middle Ring Dart (Lightning): Ranged Weapon Attack: +8 to hit, range 60/240 ft., 1 target. Hit: 10 (1d10 + 4) Lightning damage.

Bottom Ring Dart (Fire): Ranged Weapon Attack: +8 to hit, range 60/240 ft., 1 target. Hit: 10 (1d10 + 4) Fire damage.

Activate Ring Exhaust: The construct can continuously emit energy from one of it's rings in an area that extends out 10 ft. from the construct. Choose the top, middle or bottom ring to emit energy from, and that corresponding ring's ranged attack is disabled until the construct uses another bonus action to end this ability. While the construct is emitting energy, whenever a creature enters the aura for the first time during it's turn or starts its turn in the aura, the creature takes 2d6 damage of the associated type that the ring would produce.