Gateways is one of those rare copycats that manages to take a successful idea and run with it, creating a game that is fun in and of itself, and not just in the ways that remind you of whatever game it is cribbing from.
Valve's success with the Portal franchise has spawned a handful of indie copycats, and with good reason; Portal and its sequel rank among some of the best and most popular puzzle games ever made. Mimicking a great game, however, comes with its own set of problems. By standing on the shoulders of giants, you... well, make it really easy to compare yourself to a giant. Sometimes, as I felt was the case with Quantum Conundrum, even those partially responsible for the original success can fail to recapture what made the original so much fun.
Gateways is a 2D puzzle platformer built on the basic premise and mechanics of the Portal series. Trapped in a wacky science lab, with no memory of how or why you are there, you romp around, solving discrete puzzle rooms with the help of a gateway gun.
There isn't much to compare between Gateways and Portal in terms of storytelling, because there is basically no story to the game. Like QUBE, the game sets up the basic mystery ("What is going on?") and more or less keeps the answer from you until the end. There is no GLaDOS equivalent hectoring you as you make your way through the world, like there is in Quantum Conundrum, which is probably for the best.
The graphics are "retro" sprites in the current indie style. In this case, I thought they were generic in the best possible way. The impressive part about the look of the game is the way it displays the portals in the 2D world. Since we are presented with the world side-on, the game takes a queue from the split screen in the recent Lego games, filling a percentage of the screen with the world from either side of a portal gateway based on your avatar's point of view. This can get really crazy towards the end game, and that is where the simple art style really shines - by not getting in the way.
No great game would be complete without compelling gameplay, which I think is the strongest part of Gateways. Like Quantum Conundrum, you gain more, interesting powers as the game goes on. These powers, once unlocked, are not limited to specific challenge rooms, which makes exploring the world (Metroid-vania style) lots of fun. While proper timing does come in to play for some solutions, I didn't feel that twitch gaming skill was required. Some of the later challenges require use of more than one power at once, which can result in some really mind-bending (and awesome) solutions.
It took me somewhere between 4 and 5 hours to beat the game, with a few optional puzzles left still to complete. I'd say this game is the best non-Portal Portal game out there. For $5, it's a bargain, and shouldn't be missed for any fans of this strange little sub-genre of puzzle games.