Create plane

You create a shadowy door  that you can see. The door is large enough to allow any creature you would like to pass through unhindered. When opened, the door leads to a plane,  no more than 500ft on all sides. you control what the area inside looks like, what it contains and how the things inside react, until a creature not created inside comes in. aditonily, you make the laws of this world, including the laws of phisics. the plane is stabilized by three crystals you must aquire from the material plane, and if the crystals are removed, the plane colapses. no object bisides objects brought in can leave this plane, and no creature you create can leave. if you choose to do so, you can banish creatures by shuting the door behind you.

 When the spell ends, the door disappears, and any creatures or objects inside the plane remain trapped there, as the door also disappears from the other side.

you can only create a one plane, but you can have the shadowy door connect to a plane you created with a previous casting of this spell. Additionally, if you know the nature and contents of a plane created by a casting of this spell by another creature, you can have the shadowy door connect to its plane instead.