Single player, by 
This is essentially a Test level, but made to be played in Single Player rather than online. As someone who never enjoyed online tests that much I appreciate that, and there's less of a sense of urgency when playing just by yourself.
The tests are a mix of standard test fare – jumps, precise sidekicks, etc – and one or two more creative challenges including one where you need to do maths. I don't understand the math clue, which tells me that the formula to figure out what the right gun number is is "[number] x 2 + 1". The number for the first block is 0, so that's 0×2+1=1 i.e. blaster, so far so good. Then the next number is 1, so 1×2+1=3, i.e. freezer? Which doesn't work, so I'm not sure what's supposed to happen here. But overall it's an okay selection of challenges, even if most of it is pretty standard.
Rather than warping back to the start of each challenge, in this level you simply die if you fail, most of the time. Lives are not infinite though, which I found really annoying. Some tests took me a few tries to figure out what I was expected to do and not having the chance to fail more than once or twice seems to only serve to frustrate the player. This was demotivating and I would enjoy the challenges much more if I could take my time trying to figure them out. It also kind of breaks the level once you reach the end of the challenges – you're supposed to shoot a checkpoint and then kill yourself to respawn beyond a wall… but what if you have no lives left at that point?
There's a bit after the challenges where you have to swim through a school of fish. This is pretty easy to do by just speeding through with maybe one or two hits. Then there's a boss, which I found way too hard and no fun at all, but I guess it could be a fun challenge if you're really good at the game. The fact that it takes place in an arena with the same insta-death spikes found in the rest of the level at the bottom feels a little cheap though.
Visually, the level is not terrible, but not that interesting either. I guess using a blocky tileset is more or less a genre requirement, in Test levels – by that standard, this one is one of the nicer-looker ones, with some effort spent on making the background look nice, for example. This level takes place on a world orbiting an oval sun. The argument that it looks right in 16:9 doesn't really work for me – sure, it does, but then everything else looks bad.
Overall, not a bad take on the test genre, but with a bit too many elements that spoil the fun for me to really enjoy playing it.
