Chorus of Ravens

You call forth a swarm of ravens that appears in an unoccupied space within range. The swarm of ravens is friendly to you and your companions for the duration of the spell. Roll initiative for the swarm, which has its own turns. The swarm obeys any verbal commands that you issue to it (no action required by you), and if you don't issue any commands to the swarm, it defends itself from hostile creatures but otherwise takes no actions. If concentration is broken, the swarm flies away.