Ventricle Razor

Ventricle Razor is an activated item added in Afterbirth.

Effects

 * When used for the first time, Isaac creates a blue trapdoor under where he is standing. The next time he uses the item, he creates an orange trapdoor under his feet. Isaac can then walk over either of the trapdoors to teleport instantly to the location of the other one.
 * Activating the item more than twice will replace the older of the two trapdoors.
 * The trapdoors can be placed in any room.

Trivia

 * The colors of the trapdoors are a reference to the Portal Gun from the Portal series whose portals share the same colors and functionality.