Trans-Material Locomotive

Upon smashing the diamond, you teleport yourself, along with six willing targets within a 30-foot sphere centered on you, to any location on the Material Plane you have visited previously. Each target, including yourself, must make a CON save or be stunned for one round. Attempting to cast this spell outside of the Material Plane will cause the spell to fail, and the casting will be wasted.

At Higher Levels. If you cast this spell using a 9th level spell slot, you can open a functional portal to your destination that lasts for 10 minutes instead of simply teleporting six people. Anyone can use the portal and they do not need to make the save.