Hello folks! 

I am making this minimalist puzzle game: https://diogo-vernier.itch.io/lights-out, in which you have to turn off all the lights, in as few button presses as possible, and in the shortest amount of time. You can play it for free, in the browser. I will probably open source it as well.

I am making it for learning purposes and for fun, and I am loving Godot Engine.  This is a bare bones prototype build, and it is missing a lot of stuff (sounds, music, random level generation, etc.). I would love suggestions on how to make the game mechanics more original, I found out this idea is pretty old haha: https://en.wikipedia.org/wiki/Lights_Out_(game). Any suggestions?

I played the game for about 15 minutes, and it kicked my butt to be honest :)

I think it's a compelling core concept for a puzzle game, and I don't think you'll need to worry too much about it being like the one you linked as long as you develop it a bit further. Here are my initial thoughts. I know it's an early prototype so some of this may be on your radar already, but I'll list everything that came to mind just in case.

• Reset button - I found myself wanting to be able to clear the puzzle and start over, especially once I learned exactly which spaces my clicks affected.
• A diagram showing new players which spaces you activate - I think you could pull this off with just one image and little explanation, and it would save a few seconds of confusion at the start of the game. It could be a nice touch.
• Level select - I can see this being useful for people who nail down a strategy for the earlier levels. Since there's no RNG, they would basically end up doing the exact same thing every time for those levels anyway. You mentioned you plan to randomly generate levels which may change the usefulness of this, but I'm not sure in what form you mean to do that, so I'll keep this point anyway.
• Visuals - If you want to distance yourself from that other game, I wouldn't use green as your primary color. It might be cool to allow the player to pick the color scheme actually, or you may find you can do some cool stuff with a completely different visual style.
• Dead Spaces - Instead of only having square grids, you can mix it up by adding dead spaces within the grids. I could see this being the simplest way to vary the gameplay.

Here are the more out there ideas that I don't know would even work, just because you want things that might make it stand out. 

• Mirrored puzzle - I'm not sure if this would work, but maybe you could have 2 grids that both register a click at the same spot, but one affects diagonal spaces or something. It would probably be impossible to solve that, but if not it would be an interesting challenge. Maybe there would be some other type of dual puzzle that would work.
• Increased radius - You could include a level where the area your clicks affect is increased to some extent
• Sensitive spots - Kind of an extension of the last one, but maybe there's a special tile that lights or darkens other tiles whenever you hit it.

The only final note I'd have is on the idea of randomly generated levels. Looking at that wikipedia article, if you're thinking of making your levels generate like in that game you'll want to be careful not to allow the game to generate impossible puzzles. Perhaps you can use the math in that article to check each generated puzzle and make sure it's solvable before presenting it to the player.  Deviations in how the puzzles are built or solved may also complicate this further, so I'd be careful to always be sure that a puzzle is solvable.

Hi Fiver Rah!

Thanks so much for playing the game and all the insightful comments and ideas. That's so valuable!

I will definitely experiment with your ideas on how to change the mechanics. Yeah, the main concern is to maintain solvability, but I really liked the increased radius and sensitive spots ideas! I think that could really work. As soon as I have something done, I'll post here again.

Btw, I also found the higher game levels surprisingly difficult! 

Hi ! That's a little cool game, I really appreciate it, nice idea ! Good job for creating it ! I totally agree with Fiver Rah, nothing more to say. Another random idea : you could have a grid where some light are already turned off. 

And yeah, I also found the higher levels difficult. I just got stuck on level 4, quite frustrating x)

It was a really unique concept with good strategy unlike other puzzle games ive played. As in it keeps you guessing. The only thing I would comment on is that the visuals were a little harsh on the eyes; especially in a puzzle game where your're fixated on the screen. Maybe use a calmer colour palette. But really. Its a beautiful job!!!