I like the visual style, the main character is very cute and well-animated, especially getting out of the tank at the start of the game and the death animation. Some of the other pixel art is also nice, although the tiles seem misaligned at times and kinda randomly thrown together. The music is also quite cool and atmospheric, especially the main theme playing throughout the game.
It took me a very long time to figure out I could attack with Left Click, as the game page didn't say so (nor did it say that attacking was even possible at all), and the game doesn't seem to make use of the mouse at all otherwise. In general, fighting sadly wasn't very fun due to the huge enemy hitboxes and the lack of sound effects, and I ended up just walking up to the enemies and mashing most of the time.
Like mentioned before, the map feels a bit like a random bunch of platforms and tunnels, and it was a bit of a chore to navigate due to everything looking similar. It was hard to make some of the precise jumps that the game expected me to do, due to touchy air controls and lack of QoL such as jump buffering or coyote time. Grapple-able ceilings are hard to tell apart from normal ceilings, and are sometimes too far above where you're standing to see, forcing you to jump around and spam grapple to progress. The requirement to recharge the wall-breaking ability seemed a bit unnecessary, considering there was always a recharge station nearby. In the end, I walked through a door to the right of the map and ended up falling endlessly into a dark void, so I guess that means I won?
Overall not a bad prototype, it's definitely playable and has the potential for an interesting story, for example: Who cloned us and why? Who was the shadowy figure with red eyes that gave us the wall breaking power? Why is the wall breaking power a syringe? It does need a lot more polish, though!