One single laser is used throughout the puzzle. There are reflector cubes used along the way to redirect the laser as you progess. There's a bit of back and forth, but really there's no excess walking. It's just a matter of jumping back down and returning through portals. It gets a bit tricky as you progress, so I would rate this between medium and hard.
Click here to download Singularity
Click here to download Singularity
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. The solution is to put that cube from the adjoining dropper on the button. It then lowers the fizzler field. You then pop a portal in the other room above the grated barrier. Push the button again and drop another cube. It then lands in that area above the grated barrier. This means fizzle the previous one. Once that cube is up there, you then portal your way up there. You then sit it on the glass flip panel. Go back down to the first cube and momentarily lift it off the button. This will cause the flip panel to open and the cube will drop down below the grated barrier.