Rift
Typically rifts only appear for a brief moment and while they fundamentally change the landscape where they appear such as removing features, typically creatures and structures, and taking them to unknown planes or by placing said features from an unknown plane onto our world. Rifts usually don’t stay long enough to create a continuous impact to the area and typically only work in one direction.
The first noted exceptions was the Sea of Glass occurrence, where are large rift opened up for a long time, decimating Shakar.