Achievement Unlocked

I will be using north, east, south, and west as reference to where you need to go. the level layout is somewhat like this:



First off, make sure you destroy everything that can be destroyed, even other characters. When you enter the level, select Bazooka Trooper as your character, as he will make this madness portion of the level far easier. Just shoot at everything you can. Treasure dropped by characters and objects will automatically be picked up, so you do not have to run over to them to pick them up. The only treasure you have to pick up are the ones lying on the ground. Do not worry about dying either, as you won't drop any treasure.
Once you've destroyed everything in sight, start doing the following:

* Uncovering holes in the ground: There are three spots on the ground that you can blow open. The first one is all the way north, by the Stonehenge structure. The second is located in the south portion of the map, where there are lots of columns (build the blue bricks into a 'G'). The third is southeast, by the dinosaur fossil, and can be blown open by using a dynamite.

* Dinosaur: After uncovering the third hole using a dynamite, go down in it and go nuts with the bazooka. After shooting of larger parts of the ground, build a dinosaur head with the lego bricks. Go to the dinosaur and build it's ribs, then it's tail. Pick up the dinosaur head and walk up the tail, and place the head where it belongs.

* Oil pump: Go to the north west to find an oil pump. Fix it twice to make it blow up, then build the lego bricks into en 'E'. Make sure you use a female character to get the blue treasure that appears on top of it after it blows up.

* 'Hidden' room in the north west: Go further north west until you see a doorway up on the wall. Switch to a female character and jump up into it. Break the glass tiles in this room.

* Camel: Mount the camel next to where the oil rig was and go a little east to find a long line of blue treasure. Pick them all up.

* Motorcycle: At the end of the camel ride, mount of the motorcycle, then drive to the racetrack in the northwest area. Start from where the gateposts flashing black and red, and drive through the track. Once they turn green, several treasure appear, but do not worry about them just yet. You have to be lightning fast, as the gates reset quite quickly, so continuously press B to accelerate through the gates. Once you pass all five gates, pick up any remaining treasure on the track. Once you've done that, go to the newly opened hole to build an 'L'. Also make sure you destroy the north portion of the hole to uncover a vent, go through as a short character and pick up more treasure.

* The Sphinx: From the track, go north east to find something that looks like some sort of ruin. Build a part of a Sphinx's head on top of it by using the lego objects blocking the vent, then go through the vent. Pull the lever here to make more lego objects fall out of a hole in the wall, then build the rest of the Sphinx head.

* Moai: After building the Sphinx's head, jump onto the two red push platforms on the wall. This will make the Sphinx's head fall down and roll to the Moai, destroying both.

* Rickshaw: A little east of the ruin you will find a rickshaw. Mount it and follow the trail of treasure.

* Huge fan: at the end of the Rickshaw route, there will be a huge fan. Go to the backside of this fan to find it's pushable controller. Push it so that it turns counter clockwise, uncovering a ruin built into the wall. Shoot the ground in front of the ruin to uncover a doorway. Walk through this and pick up the treasure in here. Go back outside and rotate the fan even further counter clockwise to uncover a huge LEGO logo, that you have to complete by building more lego bricks onto it.

* Restricted area: From the fan, go south to find an enemy gate. Use an enemy character (such as the Bazooka Trooper) to open up a gate with some goodies.

* Mine cart: A little west of the restricted area, there's a mine cart on a railroad. On a slightly raised platform there will be two different sets of lego bricks you can build. Build both objects, then destroy them. The southern object reveals even more lego bricks that can be built to complete the box of lego. Pick this box up and place it on the cart. Pick up the torch nearby, and walk behind the cart to set it off.

* 'Chocolate' LEGO figures: Near where the mine cart was, there will be a rotator which became active after removing the bricks on the elevated part. Rotate it to uncover several figures. Destroy them all.

* Flying machine: A few stept west of the mine cart area, build all of the lego bricks into a flying machine. Apart from netting you some treasure, it serves no purpose.

* Trophy: Even further west, there will be red and yellow bricks lying on the ground. Build them to complete the trophy on the ground.

* Go north to where the Stonehenge structure was. Make sure you build the small studs lying on the ground into flowers. Use a digger near the two monkeys to uncover a small hole with yellow bricks in it. Build them to construct an 'O'. Also walk through the gate here and kill the character appearing.