You mentally grab an adjacent bubble of empty extradimensional space and stretch it so that it connects locally. The shelter has a single entrace on the plane on which it was created. The entry point looks like a faint shimmer in the air that is 7 feet in diameter. You and other creatures can enter the shelter at will. The shelter holds up to seven creatures of Large or smaller size.
From inside the shelter, you can look out of the entrace as if you were looking through a window. However, creatures in the shelter are hidden, beyond the reach of power (including clairsentient probes), unless those powers work across planes. Powers cannot be manifested across the extradimensional interface, nor can area effects cross it.
Once inside the shelter, you can take a standard action to will the exterior entrace to become invisible on the plane on which it was created. You can still see out of the entrace, but creatures on the plane of origin can't see in, even if they're able to discern the shimmering entrance itself.
When the power ends, anything inside the shelter is expelled.
For every additional power point you spend, the shelter can hold one additional creature of any size.