Yak's Hole

You touch a spot on the ground (dirt or stone), and a 5'x5' hole appears, opening to an underground room 15ft radius. The room has one chimney hole. A few feet away, a stone has appeared. It is covering the entrance. You chose any number of creatures that may enter. Any one else can see the entrance and chimney hole but can not enter. No spell can enter or exit the hole as well. After 9 hours, any one still in the hole takes 1d8 bludgeoning damage and is expelled to the top through the chimney hole. Any items left are buried 20ft down.

At higher levels you can extend the spell duration at 5 level 24 hours at 9th level 1 month.