This idea is very interesting. I think it has great potential!
The character sprites looked great, The Roulette wheel looks great.
Biggest problem was the legibility of the UI.
It was a little straining for the eyes to make out what the text was saying.
I wish there was healthbar on my character too.
Attack, Defend, Chips should all be their own easy to read UI elements with like an icon or something.
There wasn't proper feedback when you got hit. I think that would be quite easy to do with just a flash on the player sprite and a damage number popup on top.
I also don't like that you pick 3 from 9. It's just too much of a wall of text and I think pick from 3 is in every game for a reason. It's too many options and things to consider for a new player and it makes it less replayable for experienced players since they can figure out a consistent strategy to always win with so many options.
Was a fun experience!