An excellent Metroid clone, this one gets almost everything right. I think the general creepiness of the world feels like the original Metroid, but the controls are more precise like the SNES iteration. I love that the game never tells you exactly where to go next, this is what's missing in today's action/adventure games (with the notable exception of the Dark Souls series).

The upgrades that allow you to progress from one area to the next constantly surprised me - I was almost always wrong about what was needed to access a new location. A few examples: you don't need missiles to open doors, you don't use bombs to blow up weak blocks, you don't roll up into a ball to get through tight spaces, and you don't get a freeze gun to turn enemies into stepping stones. There were a couple exceptions, but for the most part the developer did an excellent job coming up with new ways to solve these old puzzles.

The music is some of the best I've heard in gaming, from any time period - dark synths with the occasional bit of creepy chanting. And the graphics, while a little bland in some of the wall/floor textures and enemy sprite designs, more than make up for any shortcomings with several rooms that are absolutely jaw-dropping. Many of the weapons also put on a nice light show, and are worth tracking down for this alone.

Speaking of weapons, most of them are completely optional, and unless you go back and thoroughly explore you won't find half of them. You probably also won't find many of the other secrets the game has to offer - I already know I didn't get the best ending, but I'm looking forward to going back in the near future.

If I had to come up with a complaint, I would say the bosses, while looking very impressive, all had fairly easy patterns that did not really change during the battles (most simply got faster as you damaged them). This is a minor issue though, and did not affect my enjoyment of the game much.

If you enjoy Metroidvanias, this one has my highest recommendation.