Map!
Well I draw a map for the Blazing sands, here it is:
[sblock=Blazing Sands]
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The more dark orange are the Blazing Dunes (often called "The Dunes" by the natives), huge sand dunes, of variable altitude. Temperature in the blazing dunes reach the 60 ºC and at night as low as -10ºC. There is no water, nor life in these dunes, save for some rare exceptions
There is only one safe way to go through the dunes, and its a path in the east, where the dunes are low in altitude, and more scattered.
The rest of the desert features cliffs and oasis (blue stars) with the predominant flora being crassulacean plants and cacti. The fauna is composed largely of arthropods and reptiles, although there are desert adapted rodents too.
Cities names:
1 Admar Pasir: a simple and plain town, it has nothing in particular to note. People of Admar Pasir live from the extraction of calcareous rock, from the nearby quarry.
2 Darnej'Far the Camels' town. A place in near the border of the desert, which flourish with the camel trade. The fines camels comes from Darnej'Far. Fortunes are lost and won in camel races.
3 Jus'Munm the white. Characterized fro it's white painted buildings, Jus'Munm is a trading post for any kind of merchandise to be transported to the interior of the blazing sands desert's towns.
4 Abde'Ragma the first. The first city you find if you are luckier enough to survive the scorching sands of the Dunes. Abde'Ragma lives from the trade, and has the same role Jus'Munm has, but from the other side of the Dunes.
5 and 6 The twin towns of Falzim'Am where founded by the grat local heroe, Falzim'Am a wizard of great power that killed the Giant Desert Ankheg. Some people say that this is a myth, and that such monster never existed. But the clusters of desert ankhegs living underground represent proofs favoring Falzim'Am's deeds.
7 The lost city of Abdu Al'Jadar. Once one of the most prolific towns of the Blazing desert, this city now lies in ruins in the central point of the desert, surrounded by The Dune. Some say it was the Giant Ankheg, that resurrected among it's kin, to bring doom to the seven settlements.
Others say that The Dune shifted and covered the entire town in the scorching sands.
No one knows for certain which was the destiny of the seventh town. Any brave (or fool) soul who ventures beyond the second twin town of Falzim'Am to the lost city never returns.
I have stated up a desert Ankheg for this area, I wasn't sure about it, and its probably unbalanced... I got the stats from the hyperlink and tried to adapt it to 4e following the DM book.
[sblock=Desert Ankheg]
The ankheg is a burrowing monster with a taste for fresh meat. An ankheg has six legs, and some specimens are yellow rather than brown. It is about 10 feet long and weighs about 800 pounds.
An ankheg burrows with legs and mandibles. A burrowing ankheg usually does not make a usable tunnel, but can construct a tunnel; it burrows at half speed when it does so. It often digs a winding tunnel up to 40 feet below the surface in the cooler sands under the Balzing Desert. The tunnel is 5 feet tall and wide, and from 60 to 150 feet long ([1d10 + 5] × 10).
Combat
An ankheg usually lies 5 to 10 feet below the surface until its antennae detect the approach of prey. It then burrows up to attack. (Treat this as a charge)
Clusters of ankhegs share the same territory but do not cooperate.
Desert Ankheg Level 4 skirmisher
Vermin large
Initiative +2 Senses Perception +16
HP 65; Bloodied 33
AC 18; Fortitude 16, Reflex 13, Will 12
Speed (land) 6
Speed (tunnel) 4
Darkvision
Low-Light vision
Resist 5 Fire

Bite (melee basic) (standard; at-will)
+9 vs. AC; 1d6 + 4 damage plus 1d4 acid damage.

Acid spit (standard; encounter)
+7 vs. Relfex; 3d8 acid damage. Hit: target weakened (save ends)
One such attack depletes the ankheg’s acid supply for the rest of the encounter. Once used, the ankheg can’t deal additional acid damage. An ankheg does not use this ability unless it is desperate or frustrated. It most often spits acid when reduced to fewer than half its full normal hit points or when it has not successfully grabbed an opponent.

Capture (standard; at-will)
+9 vs. AC; 1d6 damage. Hit: Target is grappled.
If the ankheg is damaged after grabbing its prey, it retreats backward down its tunnel at its land speed (not its burrow speed), dragging the victim with it.
Alignment Neutral
Str 21, Dex 10, Con 17, Int 1, Wis 13, Cha 6
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