Weird cliff terrain bug

[Zulaika]

It goes away when I press V. But when I turn it off it comes back.

I changed duplicate of the mineral's model but it's still a mineral.

 

[Dr Super Good]

It goes away when I press V. But when I turn it off it comes back.

You need to hide the terrain underneath the actual cliff walls. The terrain in SC2 (just like in WC3) uses a uniform vertex mesh. As cliffs are required to disrupt this uniform mesh inorder to add their model they need to hide the terrain underneath otherwise the above happens (standard vertex mesh intersects the cliff).

I changed duplicate of the mineral's model but it's still a mineral.

This is why you should avoid abusing the duplicate feature. What has happened is somewhere your "duplicate of the mineral" is not referencing the model you think it should be.

The only solution to this is to check all the links and make sure that the model you actually altered is linked to the mineral model. Also make sure you have changed the model file that the model references.