There is a missing tutorial for it, but you use the planar shift by placing it, then re-activate to teleport to it, it's a player-placed "checkpoint" that preserves your momentum so you can advance further
Oh, I may try again later. BTW, I didn't have time to make a linux build. I posted a video of the soluton of my game but if you don't want to spoil it and prefer to try yurself I may try to find the time later today.