I'm making a scenario in which i need to make a realistic desert terrain. I know you can choose desert on terrain butit seems to me that all you can use as objects are the two dirt mountains rocks and ore. HOw would you use tese to create a beleivable terrain without being to repetitive or are there other objectsyou can use?

Here are some elements you may add:

Some elevation (sand dunes)
Mixed terrain features (use some dirt, etc.)
Plants (Gaia/Objects)
Ruins
Oasis's -a small (2x3 tiles) lake of Shallow Water and some Palm Trees
The "Desert effect"; Players take damage out in the sun and have to rest in oasis's and shady mountain ranges (or inside mountain caves;)).