Selfish Sage

Divine Power Words: Your power word spells are law. Your power word spells can’t be stopped by any means, which include antimagic fields or counter spells and have their range doubled. Your power word spells with thresholds have their thresholds increased by 100 and can affect up to any number of creatures with 19 or less maximum hit dice within range. Each Power Word spell is enhanced in the following ways:

Power Word of Supreme Healing - Your Power Word: Heal spell now removes all levels of exhaustion from a creature, restores any and all missing limbs and organs, and removes any curses, diseases, and poisons from the creature.

Power Word of Annihilation - Your Power Word: Kill spell now causes all creatures that would be immune to instant death effects to be unable to take actions or move for one minute as the magic overwhelms their being. Any creature killed by this spell is devoured and can only be brought back by a True Resurrection spell or higher.

Power Word of Agony - Your Power Word: Pain spell now affects creatures that are 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. 

Power Word of Petrification - Your Power Word: Stun spell now inflicts the Petrified condition on all creatures within the hit point threshold.

Divine Serpent: You may use your Shapechange ability without expending any charges and without concentration. You retain this form in areas of antimagic 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. Creatures you choose may enter your demiplane by crawling inside your mouth while you are in serpent form.

Serpent’s Lair: Your Demiplane may grow or shrink to any size you desire. Your demiplane 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 they have. 

Rejuvenating Power: When you use your Eldritch Master feature, you regain all power charges on your Staff of Ultimate Power. 

Empowered Defenses: Your Power Defense now increases your AC by 2 per charge spent until the end of the turn.

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

Legendary Actions: 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.

Cantrip: (1 Action): You may cast a cantrip.

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

Dimension Door (2 Actions): You may cast Dimension Door without expending a spell slot.

Pact Siphon (2 Actions): You may expend a pact slot to regain 10 charges on your Staff of Ultimate Power.

Power Word (3 Actions): You may cast a Power Word spell without expending charges as a free action.