Event Horizon

Call upon the immense powers of the void and create an a zone that stuns and crushes anything caught inside. All creatures in a 40 area centered on you must make a Constitution saving throw or be stunned, they may repeat the saving throw on the end of their turns. While concentrating on this spell, you can not take any other actions.

At the start of any creature inside the zone's turn they take 2d10 bludgeoning damage. If and when a creature succeeds a saving throw they are no longer stunned but still suffer the damage as long as they stay in the zone.