Source: Player's Handbook

Level 4 Conjuration (Druid, Ranger, Wizard)

Casting Time: Action
Range: 90 feet
Components: V, S, M (air, a pebble, ash, and water inside a gold-inlaid vial worth 400+ GP)
Duration: Concentration, up to 1 hour

You call forth an Elemental spirit. It manifests in an unoccupied space that you can see within range and uses the Elemental Spirit stat block. When you cast the spell, choose an element: Air, Earth, Fire, or Water. The creature resembles a bipedal form wreathed in the chosen element, which determines certain details in its stat block. The creature disappears when it drops to 0 Hit Points or when the spell ends.

The creature is an ally to you and your allies. In combat, the creature shares your Initiative count, but it takes its turn immediately after yours. It obeys your verbal commands (no action required by you). If you don’t issue any, it takes the Dodge action and uses its movement to avoid danger.

Using a Higher-Level Spell Slot. Use the spell slot’s level for the spell’s level in the stat block.

Elemental Spirit
Medium Elemental, Neutral
Armor Class: 11 + the spell’s level
Hit Points: 50 + 10 for each spell level above 4
Speed: 40 ft.; Burrow 40 ft. (Earth only); Fly 40 ft. (hover; Air only); Swim 40 ft. (Water only)
STR (Mod/Save) DEX (Mod/Save) CON (Mod/Save) INT (Mod/Save) WIS (Mod/Save) CHA (Mod/Save)
18 (+4/+4) 15 (+2/+2) 17 (+3/+3) 4 (-3/-3) 10 (+0/+0) 16 (+3/+3)
Resistances: Acid (Water only), Lightning and Thunder (Air only), Piercing and Slashing (Earth only)
Immunities: Immunities Fire (Fire only), Poison; Exhaustion, Paralyzed, Petrified, Poisoned
Senses: Darkvision 60 ft., Passive Perception 10
Languages: Primordial, understands the languages you know
Challenge Rating: None (XP 0; PB equals your Proficiency Bonus)
Traits
Amorphous Form (Air, Fire, and Water Only). The spirit can move through a space as narrow as 1 inch wide without it counting as Difficult Terrain.
Actions
Multiattack. The spirit makes a number of Slam attacks equal to half this spell’s level (round down).
Slam. Melee Attack Roll: Bonus equals your spell attack modifier, reach 5 ft. Hit: 1d10 + 4 + the spell’s level Bludgeoning (Earth only), Cold (Water only), Lightning (Air only), or Fire (Fire only) damage.