Colossus of Gond

Statuesque: While the Colossus is unmanned and still, it appears as a large statue to the unaware observer.

Frightful Presence. The first time a creature sees the animated Colossus, it must succeed on a DC 14 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 the Colossus's Frightful Presence for the next 24 hours.

Under-carraige: The Colossus has a 20 foot tall under-carraige. Large or smaller creatures can occupy the same space as the Colossus and are invisible to the Colossus and creatures inside.

Gigantic gait: The Colossus can step over obstacles 5 feet wide, crush minor obstacles, and passes elevation changes up to 10 feet as though they didn't exist.

Secret hatch: The Colossus has a secret hatch that can be found with a successful DC 20 perception check. 

Cabin crew: The Colossus requires one sentient creature to operate (large or smaller), and the cockpit can hold up to one more large creature, or two medium creatures. The cockpit is entirely enclosed, but can be accessed by the secret hatch. Except for small holes to see outside (in all directions except down), creatures cannot attack, cast, or otherwise act upon the outside battlefield except through the actions of the Colossus itself. A creature may choose to leave the cockpit at the beginning of the Colossus's turn.

Terrible fall: If the Colossus is destroyed, roll a d4. The Colossus falls in the direction rolled, beginning with 1 for North and proceeding clockwise. Creatures inside an within a 15 x 60 foot area take 8d8 bludgeoning damage. Creatures within the fall zone are pinned and considered restrained, prone, and heavily obscured

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

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

Magic Weapons. The Colossus's weapon attacks are magical.

Siege Monster. The Colossus deals double damage to objects and structures.

Multiattack. The Colossus makes two kick attacks.

Kick. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 18 (3d6 + 9) bludgeoning damage. The creature must succeed on a DC 18 Strength save or be knocked 10 feet back and knocked prone.

Earthbreaker. The Colossus strikes the ground with it's huge hammer. All creatures adjacent to a point within 10 feet of the Colossus (excluding the Colossus itself) must succeed on a DC 17 Dexterity saving throw or take 24 (3d8 + 9) bludgeoning damage and be knocked prone. Creatures who succeed take half damage and are knocked back 5 feet. The point chosen becomes difficult terrain.

Lightning Discharge (Recharge 3–6). The Colossus exhales lightning in a 90-­foot line that is 5 feet wide. Each creature in that line must make a DC 16 Dexterity saving throw, taking 22 (4d10) lightning damage on a failed save, or half as much damage on a successful one. The creature loses it's movement for the remainder of the turn.

The Colossus can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The Colossus regains spent legendary actions at the start of its turn.

Electrify chassis. If the Colossus's currently has it's Lightening Breath ability (e.g. after rolling to regain the ability), then the Colossus’s chassis is electrified. The next creature that touches the exterior of the chassis, such as through a melee attack, takes 11 (2d10) lightning damage. The effect is discharged if the Colossus uses its Lightening Breath action or comes in contact with water. If the effect is discharged, the Colossus also temporarily loses it's Lightening Breath action, as though that action had been used.

Awaken construct (Costs 2 actions). The Colossus emits a deep hum. On a successful DC 13 wisdom check, a construct within 60 feet becomes awakened and charmed. The DC increases by two for each time the creature has been charmed on the same day.

Stomp. The colossus stamps the ground. Each creature within 10 feet of the Colossus must succeed on a DC 17 Dexterity saving throw or take 10(1d6 + 7) bludgeoning damage and be knocked prone.