How do I get through The Final Hurdle with 3 cubes?

Question

How do I get through the room The Final Hurdle to the point pictured with all 3 cubes?

Three cubes, four slots

(picture taken from There are 4 slots but I have 3 blue cubes. How do I open this door?)

murgatroid99 · Accepted Answer · 2013-02-01 20:54:32Z

First, put one cube in the slot that opens the first door First slot Then walk through the laser that opens the red doors Red door laser Next, block off the other laser with the two blocks you have Second laser blocked off Then, walk past and take both blocks Past the laser with both blocks Use one block to prop up the last door Propped up door Use the other block to jump over the laser that you previously blocked off Laser jumping block After you are past the laser, grab the block and use it to prop up the first door Other propped up door Then grab the first block, and run back through, grabbing each block as you pass it. enter image description here Success!