I was going to leave a somewhat harsher review but then I saw that the game was made ENTIRELY by one guy so given that it's a pretty good game!

GOOD THINGS
1) Very interesting and fun boss fights! Absolutely loved them!
2) You rely heavily on weapon's abilities to progress through the game and that pushes you to try and experiment with every one of them

BAD THINGS
1) The minimalistic color palette is nice, but it sometimes makes it hard to understand the environment
2) As I said you rely heavily on your weapon abilities, but:
a. You can only equip two at a time, being able to cycle through all of them would be better imo
b. There are only about 5-6 (there are two bows but you forget about the first one once you get the second)
3) The game immediately sends you to NG+ once you beat the final boss
4) The passive-ability level up system is kind of... useless? If I understood correctly you get a "level up point" (atonement) only after defeating bosses, which is ok, but it means that you get at most about 10 (If i remember correctly), while:
a. There are 9 basic abilities (+ 2 special ones I think?)
b. Every one of them has 5 upgrades, but to upgrade one you first have to upgrade all the previous ones

I have to admit that there might have been huge hidden areas or something that I didn't discover (because I wanted to explore more after the final boss), so let's say that the review is only about the main game and might not be complete.


What I mean by entirely: game design, programming, art, animation (at least that's what end credits say)

More like Unworthy of being in my Steam library, am I right, folks?? Well, unfortunately, it's now there forever.
Unworthy is a bad metroidvania primarily because of its poor traversal and overly punishing design choices, and while there's no shortage of things to nitpick here, I'm gonna focus on those.

So the game proudly boasts on its Steam page that there is no jumping to be found (for you, anyways) and they are not joking. The other claim is that Unworthy is “combat-focused”. The choice to have no jumping actually ends up hindering the combat, if you ask me, because things feel extremely shallow if my only choices are dodge-rolling and attacking. Hollow Knight's combat isn't exactly the deepest around, but the mobility of the Knight makes things more fun and tense as there's the second Y dimension for you to move around and attack in. Opening that up for you also opens it for enemies, meaning diversity in the combat; Unworthy has you and your enemies always planted on the ground (except for very rare exceptions) and eventually resorts to absurd attack patterns -- like sweeping lasers -- just to have the tenth enemy feel different from the first. It doesn't work well.

Combat is massively restricted due to this choice and getting around the map is a pretty big pain in the ass as well. If you wanna walk back somewhere, you can't just dodge enemies in the way as some will sprint after you, or fire projectiles that never despawn, or just set you ablaze with lasers. Enemies with shields can block you from rolling by and an archer behind them will fire through the shield lad entirely, hurting only you. Elevators won't work with enemies nearby and they can attack you off of ladders. Getting anywhere will always be arduous.
You best start believin' in ladders and elevators, Unworthy: you're on one! and you will be all the god damn time. Eventually you unlock a bow that teleports you to where it lands and this is as close as you get to jumping. I didn't like the spirit bow and found it especially annoying how poorly it responded to mouse input. You can only swap between two weapons, too; so you can either make that one weapon and always have the bow equipped, or constantly re-equip the thing whenever there's a frequent gap or ledge. Either way, you lose something, and it's simply frustrating.
They withhold the ability to teleport between bonfires (it's “soulslike”, so they're bonfires regardless of what they actually are) for such a long time, I began to believe it simply wouldn't ever happen. The placement of the bonfires is atrocious, too, such as one that forces you to go through a room with several enemies (near-impossible to dodge, mind you) before you can get to the area boss. To get around this problem, I had to unlock a secret area that only opens at real-time midnight to get a bonfire that still required a bit of a walk, but was free from pricks. I did not like this.
I had more fun with Unworthy when I finally looked up a map of its world to find the runes and health potions hidden from me. Sticking a majority of the upgrades necessary to keep your sanity hidden behind false walls or in rooms not shown on the map was cruel as hell, especially since, again, the traversal sucks. A couple hidden upgrades? Sure, but you should keep other bonuses hidden back there, not all the vital things.

I wanted to like the grayscale, it was quite the choice and definitely sets a mood, however there's no denying it's limiting on how your areas will look. What's different between the Catacombs of Ur and The Undercity? Believe it or not, they're both gray, so they both look like concrete. How exciting.
The final area/boss fight is the only place to introduce color, and while the juxtaposition obviously has an effect, I think it just looks incredible with that magma-colored flair. I feel this could have been done in other areas (with different colors) and the game still would have been just as annoyingly edgy. You don't just croak, here: the Grim Reaper flies by and slices your head off every time you die and text reminds you that you're “Unworthy”. You can add some green to Thornvale and trust me: your game will still be “dark”.

The game encourages multiple playthroughs and I'm not sure I'm masochistic enough to do the secret ending. For me, when a game is hard, it'll roadblock you for a while yet when you do conquer that boss, you feel like you earned something. I never felt that “reward” sensation here, it just meant the game wasn't over yet and there was more shit to get through. Beating the game didn't have me feel complete, it was more like a bittered relief.
I did like the Soulflame Gauntlets as a weapon, though. In a game where you are more mobile, they'd be really fun. They're wasted here.

I do not recommend Unworthy.