Conjure Monster

You summon an aberration, celestial, fey, fiend, elemental, or undead of challenge rating 1 or lower, which appears in an unoccupied space that you can see within range. You can choose what kind of creature you summon. The creature disappears when it drops to 0 hit points or when the spell ends.

The creature is friendly to you and your companions for the duration. Roll initiative for the creature, which has its own turns. It obeys any verbal commands that you issue to it (no action required by you). If you don't issue any commands to the creature, it acts according to its nature.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, you can conjure a monster with a challenge rating equal to half the level of the spell slot, rounded down.