The Elemental

You have forged a bond with a spiritual entity belonging to one of the 4 primordial attribute.
You happen upon one of these four spirits:
.DRYAD: A tall-sized wooden elf born from a world-tree.
You bear a tattoo of flowery tendrils on your face & neck.

.SALAMANDER: A tall-sized red dragon with scales made of flames.
You bear a tattoo of clawed flames on your chest & belly.

.SYLPH: A tiny-sized green fairy wielding a singing horn.
You bear a tattoo of 4 wings on your scapulas & back.

.UNDINE: A tall-sized merfolk dressed in a waterfall.
You bear a tattoo of water streams on your arms & legs.

Expanded Spell List

1st-lvl Elemental feature
The Elemental lets you choose from an expanded list of spells when you learn a warlock spell.
The following spells are added to the warlock spell list for you.

Spells    DRYAD                SALAMANDER         SYLPH                       UNDINE
1st         Goodberry          Hellish Rebuke         Zephyr Strike            Create/Destroy Water
2nd        Spike Growth     Dragon's Breath       Cloud of Daggers     Snilloc's Snowball Swarm
3rd         Plant Growth     Fireball                      Wind Wall                  Tidal Wave
4th         Aura of Life       Wall of Fire                Storm Sphere           Control Water
5th         Tree Stride        Flame Strike              Control Wind            Maelstrom

Solicitation

6th-lvl Elemental feature

You can conjure a spirit under the service of your elemental.
.Available once per long rest for 1h total. It returns sooner if their HP drops at 0.
If they return early, you will always be aware.

.They have their own turn in a round and will follow your orders.
If you are out of sight, they will still be active doing self-preservation.

-DRYAD: You summon a Treant Sapling.
It becomes a Treefolk at lvl 14.

-SALAMANDER: You summon a Red Dragon Wyrmling.
It becomes a Young Red Dragon at lvl 14.

-SYLPH: You summon a Chernomoi.
It becomes a High Fae Mage at lvl 14.

-UNDINE: You summon a Merfolk Salvager.
It becomes a Sea Fury at lvl 14.

Unison

10th-lvl Elemental feature

You can now assimilate the spirit into your soul, surging with an arcane form.
1 action to transform, once per long rest for 4 min.

-Blossoming Robe: You are wrapped in vine weavings, you grow flowery antlers.
.AC of 18.
.The vestigial wings on your back give you the Feather Fall spell
.Resistance to acid, bludgeoning & poison damage.

-Hellblazing Scales: Your entire body surface is wreathed with flaming scales.
.AC of 16.
.In a 12 ft/4 m radius centered on you, enemies receive 4d4 fire damage.
.Your dragon wings give you a 26 ft/8 m flying speed.

-Anemoi Feathers: Your silhouette becomes golden, covered with luminous feathers.
.AC of 14.
.Your 4 insect wings give you a 46 ft/14 m flying speed.
.Your bow & arrow deal 2d20 piercing damage in a 98 ft/30 m linear range.

-Merlord Shell: Your equipment turns into an articulated armor of solid water.
.AC of 16.
.The webbed-wings on your hips lets you walk on water.
.Your jousting lance does 2d8 cold damage.

Paracelsior

14th-lvl Elemental feature

By connecting with their primordial factor, you gain powers that purify malice & destroy evil.
The features are added to your Unison.

-ADVERSITY:
.When you run out of spell slot, you roll 1d4 to regain as much.
.Advantage on earth/fire/water/wind spells.
.You add your CHA modifier to your spell's damage.

-EXORCISM:
.Aberrations, fiends, monstrosities & undeads are vulnerable to your attacks.
.You add 1d6 radiant damage to your spells.