The Snake Sage

P2

The Legendary Serpent - You may use your Shapechange ability without expending any charges and without concentration as a free action once per turn. You retain this form regardless of any circumstances or effects, and cannot be forced out of this form unless you choose. Furthermore, you may grapple or swallow any sized creature and have no limit on the number of creatures you can swallow. Your attacks in this form now use your Spell Attack modifier instead, you may replace spell attacks with one of your serpent form attacks, and your spell attacks may grapple creatures if they hit as if constricting them. Creatures you choose may enter your demiplane by crawling inside your mouth while you are in serpent form. Your demiplane may grow or shrink to any size you desire and creatures cannot leave your demiplane by any means except your permission. It is considered a part of your domain. Any friendly creature you choose that completes a short rest within your domain regains any expended spell slots and abilities they have.

You also gain the following legendary abilities

Legendary Resistance (3/Day):  If you fail a saving throw, you can choose to succeed instead.

Legendary Defense (3/Day): If you are hit by an attack, you can choose to make it miss instead.

Legendary Actions (3: You can take legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. You regain spent legendary actions at the start of your turn.

Strike: (1 Action): You may cast a cantrip or make an attack.

Teleport (1 Action): You may teleport between 60 and 200 feet to an unoccupied space you can see.

Shed Skin (1 Action):  End 1 effect, condition or ability affecting you.

Pact Siphon (1 Action): You may regain 10 charges on your Staff of Ultimate Power or a pact slot

Power Word (1 Action): You may cast a Power Word spell without expending charges as a free action.

True Ultimate Power - The total number of charges on your Staff of Ultimate Power is now doubled and recharged on a short rest or when you use your Eldritch Master feature. It has become a part of you, no longer requires attunement, and cannot have its properties suppressed, stolen, copied, negated, or otherwise removed by any means. Your spells can’t be stopped, undone, negated, suppressed, avoided, or prevented by any means, function in areas of antimagic or no magic, and have their range doubled (if they have a range of touch, their range is extended to 120 feet). Your power word spells have their thresholds increased by 200, can be cast without expending charges, and can affect any number of creatures within range. Each Power Word spell is enhanced in the following ways:

Power Word of Supreme Healing - Your Power Word: Heal spell now also removes all levels of exhaustion from a creature, restores any and all missing limbs and organs, and removes any curses, diseases, poisons, and hostile effects from the creature as if Wish were cast.

Power Word of Annihilation - Your Power Word: Kill spell now causes all creatures that would be immune or otherwise ignore its effects to be unable to take actions or move for one minute as the magic overwhelms their being. Creatures who are above the hit point threshold lose hit points equal to the damage or hp loss of their most powerful attack, spell, or ability x 10. Any creature killed by this spell is devoured and sent to your domain as their body is reduced to nothingness.

Power Word of Agony - Your Power Word: Pain spell now affects creatures immune to the charmed condition. Any creature under the effects of this spell automatically fails any ability checks, attack rolls, or saving throws they make except for Constitution saves for the duration of the spell. Creatures above the hit point threshold instead gain vulnerability to a damage type of your choice until the end of your next turn, overwriting any prior absorptions, immunities, or resistances they may have had.

Power Word of Petrification—Your Power Word: The Stun spell now inflicts the Petrified condition on all creatures within the hit point threshold. Creatures above the hit point threshold instead find themselves disoriented and confused, coming under the effects Slow and gaining a penalty to their rolls equal to your charisma modifier until the start of your next turn.

P4

Sage Arts - Whenever you cast a spell or make a spell attack, you gain a stack of Sage Arts. For each stack of Sage Arts, your power word thresholds increase by 20, and your spell save DC, spell attack, and spell damage increase by 2. At the start of the initiative, the number of Sage Art stacks you have reset to 0. 

The Serpent’s Lair - Creatures within your demiplane and your domain find that they do not need to sleep or perform light activities to rest. Instead, they may spend 4 hours performing any activity that gives them a sense of pleasure or fulfillment to receive the benefits of a short or long rest. Lastly, you and all creatures within 120 feet of you gain a bonus to charisma checks equal to your charisma score.

P6

Warden of the Desert- Khasfan and other territories you control are under your divine protection and watchful gaze. You know all creatures that enter Khasfan and territory you control and may know their thoughts and actions. Creatures within Khasfan and territory you control cannot hide from you by any means. You may adjust the terrain, climate, weather, and other features of Khasfan and territory you control as you need as an action.

Gifts of the Desert - Creatures within territory you control may offer up a prayer to you for guidance and protection. If you choose to answer this prayer, that creature may receive the benefits of the Heroes’ Feast as well as find a Mordenkainen’s Magnificent Mansion within 10 feet of them.

P8

The Laws of Power - The hit-point threshold of your Power Word spells is now infinite. As an action, you may utter a commandment or a rule that applies to any number of creatures you choose. That rule becomes a fundamental law of reality for all creatures you choose. Creatures cannot violate this rule by any means. You may end or alter this effect as a bonus action.

Eternal Paradise - While within your domain, creatures do not need food, water, air, or rest. They may alter their appearance, physical characteristics, gender, and all other aspects of their appearance at will. They do not age, nor does time pass. When a creature leaves your domain, they revert back to their original form and do not retain any changes to their physical appearance made within the domain.