Shared Resistances. When you summon the spirit, choose one of its Resistances. You have Resistance to the chosen damage type until the spell ends.
Multiattack. The spirit makes a number of Rend attacks equal to half the spell's level (round down), and it uses Breath Weapon.
Rend. Melee Attack Roll: Bonus equals your spell attack modifier, reach 10 feet. Hit:1d6 + 4 + the spell's level Piercing damage.
Breath Weapon. Dexterity Saving Throw: DC equals your spell save DC, each creature in a 30-foot Cone. Failure: 2d6 damage of a type this spirit has Resistance to (your choice when you cast the spell). Success: Half damage.