This is a smaller Metroidvania whose roots are both Metroid and of all things Mega Man, and after having played through the game I have to wonder why nobody else thought of this before, as it is such a great match. You don’t collect any new items, only HP updates and updates to your weapon (number of shots, reload-speed and new weapon capabilities) which will help you get around various hard-gated areas. Actually the game has two kind of hard locks, those you open with updates to your primary weapon and those gates that open once you’ve beaten certain bosses.
While you don’t get new weapon capabilities after beating every boss (only from four of the eight bosses), the ones you get help you overcome various obstacles (use ice shot to cool down lava, fire to melt snow and icicles and so on). Another unique element of the game is that you don’t get double or triple jump, but instead use your cannon to get multiple jumps (another Metroidvania who did something similar before is Rex Rocket).
Aesthetic-wise this is all NES-era graphics, which I find quiet lovely. The levels and the whole game itself isn’t very big, I managed to beat it under one hour on my second-run and most of the time was spent dealing with the bosses. Those come in two categories, too easy, once you figure out their pattern (the snow level boss seems almost impossible until you get the pattern and then it’s hilariously easy) or challenging. Strangely enough, of the eight bosses only three are of the second category, the second boss, the green ninja and the final boss.
I would say the overall difficulty is moderate, not completely a walk-in-the-park, especially the three mentioned bosses keep up a fight, but far from the more challenging Metroidvania’s of recent times, like Rex Rocket or Environmental Station Alpha. That said, while it’s a small game, it’s one that gets all the essentials right and packs a lot of fun into its running time.
If you want to get 100% for items, I’ve marked the three not so obvious secrets with orange squares on the game map. There are a couple of other secrets, but mostly behind rather obvious fake walls.