Combine Strider

Towering Height. All creatures smaller than the Combine Strider must roll disadvantage when making a melee attack from the ground.

 Legendary Resistance (1/day). If the Combine Strider fails a saving throw, it can choose to succeed instead.

Stomp. Melee Weapon Attack: +8 to hit, reach 10 ft., 1 target. Hit: 20 (2d8+11) piercing damage. Any creature smaller than the Combine Strider must succeed a (DC 14) constitution saving throw or be knocked prone.

Pulse Cannon. Ranged Weapon Attack: Always hits, range 150 ft. line, three shots, multiple targets. Hit: 6 (1d4+4) force damage.

Legs. The Combine Strider can spend its bonus action to stand tall or crouch.
When standing normally, a Combine Strider takes up a 15x15 ft. space and is 50 ft. tall.
When standing tall, a Combine Strider takes up a 10x10 ft. space and is 75 ft. tall.
When crouching, a Combine Strider takes up a 20x20 ft. space, and is 25 ft. tall.

Dash. The Combine Strider may spend its bonus action to move up to double its walk speed.

At the end of another creature's turn, the Combine Strider may choose to make a legendary action. The Combine Strider may make up to a total of 3 legendary actions each round. When a legendary action is used by the Combine Strider, it may not be used again until the Combine Strider's next turn.

Stomp (Costs 1 Action). The Combine Strider makes a Stomp attack.

Pulse Cannon (Costs 1 Action). The Combine Strider makes a Pulse Cannon attack.

Warp Cannon (Costs 3 Actions). The Combine Strider charges its beam at a target of its choice. This target can be a creature, construct, or surface. The beam is 100 ft. long and 5 ft. wide. Any creatures inside the beam or within a 15 ft. circle of the point of impact must succeed a Dexterity saving throw (DC 17) or take 28 (4d12) force damage on a failed save as well as being blinded for 2 turns. In addition, any non-magical objects or surfaces with an AC less than 18 will be destroyed. Any walls or surfaces that are destroyed will become difficult terrain, and also become burning hazards.