Ugrerkobbbog

A name feared in many universes, the being has no known origin. It only hunts before dragging them through a portal and squeezing them into a square.

If you find a square in your dimension it means it is always close by in another. To survive this entity there is not much you can do, but if the ugrerkobbog touches light it will vanish into thin air. It is not known to be able to communicate in any language, but it is an intelligent being. Maybe even more so than yourself, why it decides to spend its existence tormenting other life forms and entities by making them into squares is beyond understanding.