Blood Machine

Vicious Engine. Whenever Blood Machine deals damage, it heals an amount of health equal to 6d4 + 2. 

Siege Monster. This creature deals double damage to objects and structures.

Battle Frenzy. When Blood Machine is at or below one-quarter its maximum hit points, it can make one additional attack on his turn. When it does so, it gains a +7 bonus to it damage rolls, but also gains a -7 penalty to it attack rolls.

Action Name. Blood Machine takes 2 ranged weapon attacks. It then uses its Frightful Presence.

Frightful Presence. Each creature of its choice that is within 120 feet of it and aware of it must succeed on a DC 15 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to its Frightful Presence for the next 24 hours.

The Machine's Guns. Ranged Weapon Attack: +5 to hit, range 60 ft., 1 target. Hit: 25 (5d10 + 5) piercing damage.

Aggressive. Blood Machine can move an amount of feet away equal to its movement speed.