StarWaves
Plot hole: If you open a portal at the bottom of the ocean, the sheer pressure it'll shoot will disintegrate many things much else humans. A waterjet that are used to cut metals have around 30,000 psi to 90,000 psi. At the bottom of the ocean, there is 15,000 psi spread out. By spread out, it means just by being there, you'll be crushed by 15,000 psi equally. Imagine if all that pressure is concentrated in one human sized hole. The burrow should've disintegrated by that point.