Conjure Planar Being

Focus to summon a creature from any plane of existence, except your own. You can summon creature of challenge rating equal to your spellcasting level.

Conjure Planar Being to appear within 10 ft. of caster. Planar Being is hostile to all creatures except caster, it cannot be communicated with or controlled. It will become hostile even to caster if caster shows any sign of hostility towards it.

It will follow it's own stat block.
Spellcaster can choose to banish the Planar Being as action or reaction. 

One spellcaster cannot conjure multiple planar beings at once.