Crimson Day

Mirrored Underbelly. Crimson day's underbelly of its slender body has the ability to coat its entire body as see through as seen down below. If crimson day starts an encounter, the mirrored underbelly will make any enemy beyond 30 feet not notice it and granting it Surprise on the enemy.

Moody Static. Crimson day will emit its presence in the sky by causing the overhead lights to be Green, if the environment is green it warns of a Crimson Day's presence, A green light from above means that Crimson Day is neutral and also making itself present for others to see. If a Bright Red glow overshadows the ground below it, it is hostile and will strike anything alive in its radius

Momentary Haunting. Crimson day has a tie to the Ethereal Plane through its physical body as long as it has a soul used as a gateway to and from. If Crimson Day speaks to an entity with an Intelligence score above 18 and takes a liking to them, Crimson day will offer to use their body as a gateway to the ethereal plane
Once a Day, The gateway user of Crimson Day has the ability to use a lesser form of Roar of the Crimson Day that deals 15d4 Force Damage and 2d6 Psychic Damage to the Caster.

Multiattack. Crimson Day reaps its targets three times with its jaws.

Jaw of Spikes. Crimson day lashes 15 feet in front of it with one of its three jaws, swiping and dealing 4d12 + 14 Bludgeoning and Piercing damage; Opponent must roll a Strength or Dexterity saving throw (DC18). On a success, the opponent is Grappled. On a failure, the opponent is Paralyzed.

Atmospheric Pressure. Crimson day concentrates the air around it in a cube 100x100 feet. A creature caught inside the pressure must roll a Dexterity Saving Throw (DC15) or move 15 feet toward the mouth of crimson day and takes 2d6 force damage no matter the roll.
Atmospheric Pressure will end if Crimson day uses Roar of the Crimson Day or is Incapacitated.

Roar of the Crimson Day. Once crimson day activates Atmospheric pressure 3 rounds prior, Crimson day can release the charged up energy in a beam of force 15 feet wide and no end point until it reaches an object a foot thick to disperse it. 
The opponent must roll a Dexterity Saving throw (DC20) and take 30d12 Force Damage or half as much on a success.
Using Roar of the Crimson Day will end Atmospheric Pressure

Engulf. Crimson Day moves up to its speed. While doing so, it can enter Large or smaller creatures' spaces. Whenever crimson day enters a creature's space, the creature must make a DC 15 Dexterity saving throw.

On a successful save, the creature instead gets knocked prone and must lay until their next turn.

On a failed save, Crimson Day enters the creature's space, and the creature takes 50 force damage and is engulfed. The engulfed creature can't breathe, is restrained, and takes 50 force damage at the start of each of the crimson day's turns for 4 turns until it is either dead or regurgitated. When the Crimson Day moves, the engulfed creature moves with it.
An Engulfed creature cannot escape unless crimson day's entire body is flat against the ground, in which they can take their movement speed to leave Crimson Day.

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Spiked Plate. If crimson day is hit by any melee attack, the attacker takes 4d6 slashing damage
Ethereal Lens. As a reaction Any enemy caster must roll a d20 plus their spellcasting modifier while crimson day rolls 5d8, If Crimson Day rolls higher, the spell will be counterspelled and expelled in a cubic area 40 from the eye of crimson day of crimson day's choosing.

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