How do I got about retexturing land. I have all grass and want to build a small mountainous area.

[Peewee Musytari]

If it is mainland you cannot change the terrain textures.

If it is a private sim, the owner or estate manager can change them in the region / estate settings (from world menu) on the terrain textures tab, but it will change the textures for the whole sim, not just one 1/4.

The other option, as you said, would be to use prims.

Depending on the 4 textures that are being used on that sim for the different land layers, it may be possible to put a rock texture on the top one so that it only high areas show as rock when you terraform.

[Peewee Musytari]

If it is mainland you cannot change the terrain textures.

If it is a private sim, the owner or estate manager can change them in the region / estate settings (from world menu) on the terrain textures tab, but it will change the textures for the whole sim, not just one 1/4.

The other option, as you said, would be to use prims.

Depending on the 4 textures that are being used on that sim for the different land layers, it may be possible to put a rock texture on the top one so that it only high areas show as rock when you terraform.

[Cinnamon Lohner]

Land textures are controlled at the Region/Estate level and not the land parcel level.  As you raise or lower land, the land will change texture based on how it is setup in the Ground Textures tab of the Region/Estate window.  So unless you own the sim or can get the sim owner to change ground textures for you, a prim mountain  might be your best option.

--Cinn