Threshold

You create a linked teleportation portal from one door frame within range to another door frame that you have seen before that is part of the same threshold network.  If either doorway has a door that is locked, the creature entering the portal must be holding a key to the lock for the portal to function.  Either door can be unlocked normally by a creature holding the proper key.  Any creature or object entering the portal exits from the other portal as if the two were adjacent to each other.

On your turn, you can end the effect as a bonus action.  While the spell is active, you can use your bonus action to create another connection between a doorway that is within range to another doorway that is on the same network.  You may only have one connection sustained at a time.

Note: Some threshold networks may require you to give a certain knock or password as part of the verbal or somatic component in the casting of the spell or said/preformed in the creation of a new portal.  Threshold networks can be created with the use of the Threshold Nexus and Link Threshold spells.