Unstable Door

An Unstable Door will, when placed, randomly connect to a Dimensional Door, Warp Door, Rift or Rift Gateway anywhere in the Overworld, Nether, Mystcraft Age, Pocket Dimension or a Gateway in Limbo.

It is a one way trip, as no matter what the destination is, you will never be able to return to the Unstable Door via the Rift, Door or Gateway that it transported you to.

Using this type of door carries a high risk of being transported to Limbo.