Magnetic presents a series of challenges that require you to transport a cube to a button on the other side of the room. Twist: those cubes are at the other side of a wire mesh, in self contained areas with no portalable surfaces, that are just close enough to be carried. The unusual set up of the puzzles led to a section that had me stumped for long minutes before I realised the solution was blindingly obvious. Download Magnetic here .
7. Path of the Cube
Something different to the usual puzzle set-up of having the Perpetual Testing stickman doing the level acrobatics. In Path of the Cube, you and your Companion Cube operate two buttons to guide a regular cube through a side-on maze full of moving platforms and excursion funnels. No portalling to be done here, but the inventiveness of the premise makes for a nice change. Download Path of the Cube here .
8. The Laser Cross
All great laser-based maps are about making your limited resources stretch further than should be possible. The Laser Cross is one of the best, forcing you to constantly revise your solution as you attempt to activate the various components of each room with just two refraction cubes. One simple mistake and you'll end up back at the start, refining what seemed like a sound plan. Just watch out for the bloody faith plate. Download The Laser Cross here .
9. Time Saving
Mapmaker Romb has a penchant for devising some of the trickiest puzzles to come out of the community. Time Saving isn't the most head-scratching of his creations, but unlike many of the others, it also doesn't rely on obfuscation or odd quirks of Portal 2's physics. Instead it's an enjoyable sequence of problems to overcome, with a timing element that's sure to please Portal 1 fanatics. Download Time Saving here .
10. Too Simple
A cube on the floor. A button connected to the exit beside it. Simple, right? Well, no, not quite. Too Simple has a devious little trick up its sleeve that blocks you from completing the obvious. Once it's revealed its gotcha, the rest of the level isn't that hard to work out, but it's a nice little timing challenge and a reminder that in Portal, nothing is quite what it seems. Download Too Simple here .
Head to the final page to see our top five Portal 2 custom campaigns.