Ancient Golden Serpent

Long ago there was a great two-headed golden serpent that was created to protect the deep wilds from unwanted hunters and travelers. When the mighty hero Zhars encountered the beast, it cleaved it in two right where its necks joined. Instead of killing the beast, the blow split it into two serpents. Impressed by the hero's strength, the snakes bowed before him and granted him passage through their woods. The snakes, who were once transformed into the guardian beast by Pan, were visited by the god once more many years later. Pan asked if the serpents would move to a new forest, to protect an important gate. The serpents agreed and were brought to the Isle of Pan, just before it was transported to The Ancient Tower. Now they guard the gate that lies in the hidden sanctuary, deep within the woods of the isle.

Traits

• Shifting Size: The serpent can change its size from small to large at will. When small its movement is 20 ft., when it's large its movement is 40 ft. Additionally, when small, any physical attacks the serpent makes only deal a quarter of the usual damage and Golden Mist's radius is reduced to 5 ft.
• Deceptive Movements: When the serpent has a higher passive Acrobatics than a creature's Passive insight, the serpent may spend an additional 10 ft. of movement to move out of that creature's range without provoking an attack of opportunity.
• Unrestricted by Nature: The serpent does not suffer any movement penalties from difficult terrain imposed by flora or natural phenomena, even when produced through magical means.
• Swift Tail Strike: The serpent may make an attack with its Tail as a bonus action, however, when doing so it has disadvantage on the attack roll.

Spell Casting

The serpent can cast spells using its Wisdom as its spell modifier (spell save DC 16, +4 to hit with spell attacks). The serpent can cast the following spells:

• Entangling Growth (twice a day): The serpent may select a spot it can see within 30 ft. Dense vegetation rapidly grows around the spot in a 30 ft. range. Creatures inside this area when the vegetation appears need to succeed a DC 16 Dexterity saving throw or become restrained. A restrained creature can spend an action to break itself free. In order to do so it must succeed on a DC 9 Strength check. The area counts as difficult terrain and withers after 24 hours.
• Armor of Thorns (one a day): The serpent manifests thorny vines all around its body. The serpent's DC is increased by 3 and is resistant to magical slashing, piercing, and bludgeoning damage. Any creature that hits the serpent with a melee attack while the thorns are active takes 10 (3d4 +3) piercing damage in return.
• Armor of Dew (once a day): The serpent manifests a thin coat of shiny water droplets covering its entire body. As long as it is coated in dew, it has advantage on saving throws against spells and other magical effects. When targeted by a ranged spell attack, the serpent may use its reaction to deflect the attack back at the target. Deflected attacks use the same attack roll minus the level used to cast the spell. If the deflected attack hits, the target takes half damage. Deflected attacks cannot crit.

Actions

• Bite: Melee Weapon Attack: +7 to hit, reach 5 ft., 1 target. Hit: 13 (2d8 + 4) piercing damage plus 9 (2d8) acid damage.
• Tail: Melee Weapon Attack: +9 to hit, reach 10 ft., 1 target. Hit: 15 (2d10 + 4) bludgeoning damage.
• Acid Spit: Ranged Weapon Attack: +8 to hit, range 60/120 ft., 1 target. Hit: 22 (4d10) acid damage.
• Restrain: The serpent reaches out with its tail, attempting to grab a creature within 5 ft. that is at least one size smaller than itself. The creature must succeed in a DC 17 Strength saving throw or become restrained by the serpent. During its turn, the restrained creature can take an action in an attempt to break free from the restraint. It must succeed on a DC 15 Strength check to do so. While restraining a creature, the serpent's movement speed is halved and it cannot benefit from Deceptive Movements. The serpent can only restrain one creature at a time. While restraining a creature, the serpent may use a bonus action to Squeeze that creature.
• Squeeze: As a bonus action, the serpent squeezes the creature that it has restrained, dealing 13 (2d8 + 4) bludgeoning damage.
• Golden Mist (recharge 4-5 turns): The serpent breathes out a faint mist in a 20 ft. cone in front of it. The mist has small golden flakes in it that scorch any creature that touches them. Creatures within the mist must succeed on a DC 16 Constitution saving throw or take 27 (6d8) acid damage. On successful safe, they only take half damage. The mist lingers for 3 turns as a cloud with a 10 ft. radius. Creatures entering the cloud or ending their turn in it must repeat the safe, taking 10 (3d6) acid damage on a failed safe or half as much on a successful safe. The serpent is immune to the effects of the mist.

Legendary Actions

The serpent may make up to 2 legendary actions each round.

• Disengage: The serpent uses the disengage action and may use up to half his speed.
• Bite
• Tail
• Acid Spit
• Spellcasting (2 actions)

STR	DEX	CON	INT	WIS	CHA
18 (+4)	18 (+4)	16 (+3)	10 (+0)	16 (+3)	12 +1)

Type: Large Beast
Armor Class: 15
Hit Points: 216
Speed: 20/40 ft.
Proficiency: +4
Saving Throws: STR +8, CON +7, WIS +7
Skills: Perception +7, Survival +7, Acrobatics +7
Damage Resistance: Slashing, Piercing, Bludgeoning from non-magical sources; Acid, Poison
Condition Immunities: Poisoned, Feared, Charmed
Senses: Darkvision 60 ft., Smell 30 ft.
Languages: Common, Sylvan, Hippodeaon, Celestial
Challenge: 10