Here is the walkthrough for Mental:
Little Green Man
* Click on the little green man and go down one level.
* Move him to the window with the vine and press SPACE.
* Move little green man to piece of paper on desk and press SPACE.
* Go back to window and climb up the vine (press SPACE).
* Go back to the top floor starting room.
* Move little green man to vent on side of wall and press SPACE.
* Climb to the rooftop and move green man to the air vent to the right.
* Click piece of paper in tool box and then press USE.
* The paper should float down the air vent to the medium sized orange man.
Medium Orange Man
* Zoom out and click on orange man.
* Move orange man to paper and press SPACE to pick it up.
* Move orange man through door to the right into the bathroom.
* Move him to the mobile phone and press SPACE to pick up.
* Click on the paper in the tool box and the press USE. Take note of the phone number.
* Click the mobile phone and then press USE. Click the number that was shown on the paper and then press call.
* The nurse should move to the ringing phone.
Big Purple Man
* Zoom out and click on the big purple man.
* Move him to the YELLOW key on the desk and press SPACE to pick it up.
* Move big purple man to the door on the back wall and go up one level.
* Move big man to the axe on the wall and press SPACE to pick up.
* Move big purple man up one more level. Move him towards the box (next to bookshelf) on the floor until it disappears.
* Move big man to the door to the left and then up one level to the top floor.
* Move big man to the door with the wooden planks. Select the axe from the toolbox and click USE.
* Move big man through the door that is now accessible (no more wood blocking it). Push through the boxes in the next room and continue to the bathroom.
* Move big man to air vent grill on wall and press SPACE to remove.
* Click on the key in toolbox and then click on DROP.
Little Green Man
* Zoom out and click on little man on roof.
* Move little green man to bathroom.
* Move little green man to key in bathroom and press SPACE to pick up.
* Move little green man to open vent in wall and press SPACE to go up.
* Move little green man to rope on roof.
* Press SPACE to throw rope over edge and SPACE again to climb down.
* Move little green man to marbles on desk and press SPACE to pick up.
* Move near window and press SPACE to climb back up to roof.
* Move back to bathroom and DROP the marbles on floor.
Medium Orange Man
* Select medium sized orange man and move to marbles on floor. Pick them up.
* Move orange man all the way to the far left room and then down a level.
* Move orange man to the room to the right and then down another level.
* Move orange man to the barred window and select the marbles from tool box and then press USE.
* The dog should drop dead.
Little Green Man
* Zoom out and select the small green man.
* Move the small green man to the floor below just next to the bookshelf.
* Move small little man to the chair next to the bookshelf and press SPACE to climb up.
* Move small little man to the manhole with the ladder and press SPACE to climb down.
* Pick up the BLUE key in the room below.
* Move small green man out of the room and back over the bookshelf.
* Move him down two floors to the starting room of the Big man.
* Move small green man to the right to the small keyhole in the wall.
* Select the blue key and press USE.
* The door on the right should be unlocked.
Medium Orange Man
* Zoom out and select the middle sized orange man.
* Move him down to the now unlocked door and go through to the barred wall.
* Click on the marbles in orange dudes tool box and press USE.
* The bars should rise. Move orange man to the key card and pick it up.
* Select small green man and move him to the window and press space to climb out.
* Once down move him to the outside keyhole and use the YELLOW key to unlock the external door.
Big Purple Man
* Zoom out and select the big purple man.
* Move him to the room with the pot plant in it.
* Move big man to the pot plant and press SPACE. The plant should be picked up and dropped out the window.
* Move purple man to the room he started in and press SPACE next to the power switch on the wall. It should light up green.
Medium Orange Man
* Zoom out and select medium sized orange man.
* Move him to the same room as big man and go to the far left room (the one where the nurse was hit in the head by the plant).
* Move down one level and move towards the boxes.
* Select the marbles from toolbox and then press USE.
* The nurse to the right should be electrocuted.
Big Purple Man
* Zoom out and select big purple man and move him down next to orange man.
* Move him to the right and push the boxes out of the way.
* Continue all the way to the right until you reach the locked door.
Medium Orange Man
* Zoom out and select the orange man and move him to key card reader near the big man.
* Select key card and press SPACE. The door should be unlocked.
* Move both guys out of the building to little green man.
Basement level…
Small Green Man
* Click on little green man and move him to the hole in the wall.
* Move him to the pipe wheel on the wall to the left and press SPACE.
* Move little green man back down to the bottom level.
Big Purple Man
* Zoom out and click on big purple man.
* Move him through door to the left and towards the chemical flask on the wall. Press SPACE to pick up.
* Move big man down one level and pull the lever on the wall and pick up the axe.
* Move him back up a level and then through the door to the left all the way to the room with the keyhole in the wall.
Medium Orange Man
* Zoom out and select the orange man.
* Move him to the marbles on the ground and pick them up.
* Then move him to the wall with the wooden planks. Select the marbles and then press USE.
Little Green Man
* Zoom out and select the small green man.
* Move him to the left and pick up the pink key on the ground.
* Move small green man up a level again through the pipe all the way to the ladder to the far left.
* Climb up ladder all the way to the air vent hole in the wall near big purple man.
* Click on the pink key and then click on USE.
* The key should fall into the room with the big man.
Big Purple Man
* Zoom out if necessary and click on big purple man.
* Move him to the key and pick it up.
* Click on key and the USE.
* The door down should be unlocked.
* Go down to same level as medium sized orange man. Move to wooden planks on wall and click on axe and then USE.
* Move the big man to the far right to the door with the metal bar on it.
* Click on the chemical flash and then USE.
* The metal should dissolve and the door will be unlocked.
* Move both guys down the door to the bottom level and then to the left to the barred wall.
Medium Orange Man
* Select medium sized man and click on the marbles and USE.
* The barred wall should lift.
* Click on the big purple man and move him to the rocks and then click SPACE
* The rocks should be removed and then move both guys out the door behind the rocks.
YOU'RE FREE!
Source: Free World Group
