Take the Fallback portal into Droughtlands and head to /setwaypoint 8403 6392 Continue north up the hill to /setwaypoint 8339 6202
The Puzzle
The Droughtlands puzzle consists of 8 cages. Inside one of the cages is the treasure chest!
You need to move the chest from this cage, along the other cages until you reach the last cage. Each of the cages acts like a teleport, to activate the teleport, you need to click the light at the top of the cage when it matches the light on the back of the cage..
Activate the cage with the chest in when the lights match, then follow the chest around and keep matching the lights for whichever cage it ends up inside, eventually you will get to the end cage and be able to loot the chest. The lights change pretty quickly, you want to ensure you click the light as soon as it changes, even if that means waiting a few seconds for it to come around again.