Death Desert is seen in Mother 3 in Chapter 3. When you play as Salsa, the monkey, you'll get dropped off here along with Fassad, telling you that he'll only free Samba by following his every command and performing.
This is an easy area. You don't even need to attack! Fassad Is a powerhouse and he can do the battles for you. There are some bugsprays around to kill the antlions. Just beat the Dung Beetles, and you'll get Dung. Go to Wan Sum Dung and he'll give you 5 EXP for each piece of Dung you give him. After you've done this, you'll find a White Building shaped like a Pig's Face. That's about it for the entire Death Desert. Two Frogs are located here, so look for them. A Giant Antlion has captured one of the frogs though. The other one is at the very beginning of the Desert, in a barrel. Go talk to him and save your game.