Let me preface this review by saying I don't think Cloudbuilt is a bad game. Unfortunately Valve only allows "Recommended" or "Not Recommended" on their review ratings. Admittedly it's better than when they only allowed thumbs up at least. But unfortunately on games I have mixed feelings on I cannot recommend them to my friends or otherwise.
Anyway, Cloudbuilt is an extremely niche game clearly built for an audience and one audience alone; speedrunners. While that focus helped make it carve out a unique character to its gameplay, its sole emphasis on that has harmed it overall for other players of the game. A lot of the levels feel like they absolutely require memorization in order to do fluidly. The controls are kind of poor as well; with more attention they would have been much, much better. Again, despite the paragraphs below complaining about flaws, I don't feel that this is a bad game. When you're not dealing with issues the game is fast-paced, challenging and extremely fun, playing much like you see in the trailer.
Since the controls are my main problem with the game I'll go over these first. The controls do work, but they FEEL clunky. At least part of this is the length of the game to learning curve ratio. The game is only about 2 hours long to the end, and you can beat most of the side missions in 3 hours. Much of that time the player will likely getting used to little nuances with the controls that are not immediately obvious from the tutorial though, like figuring out that you can air control like in a 2004 game where back instantly stops you. Mixed in is some legitimate clunk too. An example: One of the gifs on the community page right now is the triple slide section from one of the more difficult levels. There is a similar section on another level that ends with you hitting a vertical wall, boosting up the top, wallrunning along the side, then up and around again all the way to the exit. The player only gets a limited amount of boost to do maneuvers like that so losing as little momentum and using the minimal amount of energy is the key to success. Unfortunately the input from the jump off the last slide to the wall is extremely unforgiving. Why? There is no slack at all in the controls. If you hit the boost button even a split second before you've made firm contact with the wall, you will instead boost into it, which will result in you smacking into it, flipping around, then sliding off to your death. In the end what you have to do is rely on visual confirmation that you're in the correct pose before you can boost up which is inefficient and waste momentum/energy. This is really the number one issue with the controls. They already have a pretty decent learning curve in proportion to the length of the game, but this one mostly likely everyone will struggle with on and on because it feels very unnatural and unconventional compared to most games. It's funny because the game has 4 or 5 checkboxes under gameplay options for changing the behavior of how wallruns work, but none to deal with this issue. The fact that those options they put in are even needed should be a red flag right there that wallruns should either be fixed or redesigned.
The other big problem with this game is level design. Memorization is required in several places, period. You are not getting past certain parts on your first try. Stuff like running through a bunch of explosions only to find a force field you need to charge shot, going through a long wallrunning section only to find a force field in your face are quite common later on. The number of times I did a wallclimb only to be smacked by an obstacle was rather enormous. Reflexes can't deal with these things and a lot of the times you have to already know what you're going to do before you do it. There's also a particular chaser enemy that has a force field and will blow up in your face, usually knocking you to your death. Just to give you more time pressure when you already don't know where to go, of course. Things like this are okay on paper but when it comes to playing through a level the first time it is incredibly obnoxious and frustrating. Part of the issue is the pink forcefield things can at times be extremely difficult to see in the air.
On the subject of enemies, I'm not really sure they really add much value to the game at all. In my opinion a lot of the fun vanished as more and more enemies were added to the levels. Only the new/bad players will be affected by the homing missile guys, the regular turrets are worthless, the melee shocker guys on the paths and the wide shooting turrets are the only real threats. Those two have a point in being in the others notsomuch. Eventually the stages start to get chock full of them and they get a bit tedious to avoid. And you have to avoid them because you have a lifebar, which is another thing that puzzles me. You have a lifebar and limited lives. You'd think the main purpose of the enemies would be just to knock you off but apparently not. And lives... fail enough and restart the level... I'd generally only get stuck on one spot on most levels so this just makes it if you get stuck too long there you have to redo the whole thing. I don't see why there are lives other than the simply fact that video games have lives and thus this game needs them too. I mean, Super Meat Boy didn't have lives...
Even with these issues the game generally works and is overall quite a fun experience if you're good enough to play it. I'm not usually a terrible fan of celshading but the game does it well enough and the music fits. Again though, it's clearly targeted at speedrunning and speedrunning alone; it took about two hours for a pleb like me to beat the game and a bunch of the side stages if that's all you're interested in. But in the process of beating it I got maybe one B and the rest were Cs or Ds. If you're the kind of person that likes to get S ranks on everything, this game is probably for you. Of course it ain't easy; said Cs were also around rank 500 on the scoreboard for many of my runs. Game is interesting, but it just needed better execution. Looks like the developers aren't going to be making any sweeping changes at this point, so I'm hoping if they make a sequel it addresses the issues I had with the game.