The questionable nature of the title notwithstanding - I'd like to think it's a play on 'invention', and not a straight out typo - Invertion is a solid browser game. Not graphically stunning, and given that it's an overt homage to Portal perhaps not entirely original, but most players should have a lot of fun in this gravity-defying title.
As mentioned Invertion pays tribute to Portal (like, right in the game's description, so don't be saying that it 'ripped off' the classic title), and consequently it boasts a plot with a helpless little lab experiment and a sadistic, female AI bent on using said experiment for tests. Unlike Portal, however, the victim in Invertion is a robot - and consequently, can generate crazy powers of his own, without needing an awesome portal gun. Including a sarcastic, villainous AI who comments on your impending death may have stretched the comparison a little too far, but I won't quibble.
Invertion's mechanics aren't fully like Portal's, anyway - I'd argue that it's actually a little tougher, owing to the robot's unique powers. Not only can the little guy perform the usual platformer tasks like running (hovering) and jumping (propelled hovering?), he's capable of generating a clone of himself that mirrors his actions - or one that reverses gravity and falls up rather than down. And every time your robot moves, so, too, do the clones. Do you have any idea how tricky it is to move four robots in tandem, all going different directions?
Well. You're about to find out.
Invertion is only simple for the first few levels. Once you acquire all of your powers, your job gets a hell of a lot harder, for not only do you have to keep track of your own guy, you need to watch over his clones, which can prove a pain in the ass around spikes, pits and other obstacles. I had no difficulty with the basic controls, though wrapping my brain around moving multiple characters in different directions simultaneously took some doing. Aside from some sliding on landings, this wasn't a problem.
Invertion's controls started to fall apart a little during the creation of clones. The game relies on Z, X and C to perform tasks, and though C's job is easy - activate items in your surroundings or go through doors - Z and X are easy to confuse because they're so damn close together, and because you're thinking about so many other things that you're bound to make a mistake. You only get one chance per level to create gravity-defying clones (and another to create inverted clones - you'll understand when you play), so screwing up the order will, invariably, force a restart. The levels aren't LONG, that said, but constant restarts will annoy some players.
Is there any way for the programmers to get AROUND this problem? Not bloody likely.
Invertion isn't the pinnacle of graphical perfection in the browser market, as the levels all look more or less the same, and nothing about them is terribly inspired. Your robot is probably the best part of the visuals, and I wouldn't say it's enough on its own to make Invertion stand out. Not BAD, just... meh.
Invertion's music starts to annoy quickly - it's a constantly-looping sci-fi techno beat that, like the graphics, doesn't stand out in any huge way. That said I DID appreciate the sadistic voice of the female AI, which, while not quite as venomous as Portal's GLaDOS, performs admirably as a passive villain. Tighter, less repetitive writing (enough about the spikes!) will probably make her truly memorable in a sequel.
As with every puzzler, Invertion's true value lies in its challenge rating. Is this game hard? And is it not so hard that it's frustrating rather than fun? I'm happy to say that both statements apply to the game. It's hard, but it's still fun.
Invertion's levels are novel. They force careful, strategic thinking without proving totally impossible to the average gamer. You'll probably spend a solid fifteen to twenty minutes apiece on the end game challenges, which is just long enough to be satisfying when you do discover the answer. There's also a link included to a walkthrough of the game, which is much appreciated if you just want to see the ending.
As far as puzzlers go, Invertion is solid. Not the best, perhaps, but a worthy enough successor to Portal as far as free games go, and an excellent way to spend an hour or two of boredom. I approve.