Dark Dwelling

Choose a spot within range. After performing a 10 minute ritual, a portal opens to a dungeon lair. The interior of the lair has 9 beds, a kitchen, a meeting room with a table, and a fireplace.  Up to 9 medium creatures can comfortably fit inside. There are no windows, and creatures inside the dwelling cannot see outside of it. For the duration of the spell, no creature may enter without being willingly invited by the caster and no magical effect can penetrate the lair, nor are any creatures not present at its creation aware of its existence. Inside the lair, an anti-magic field prevents any spells from being cast and negates all magical effects from magic items. 

Creatures who willingly choose to leave before the spell ends cannot find their way back inside. At the end of 24 hours, all creatures inside are teleported back to the portal's original location.