Go to forge, go in one of the bases on Avalanche.

Buy a two way teleporter, then put it in the base.

Then behind you, if you spawn in the base where it's dark, be oracle (ball mode) then face the part where it's dark.

Go in front of the window so you touch it when you're facing it.

Then buy another teleporter and it should be on the other side of the glass.

Go through it.