ok I have one thing to say the theme is goodish but ALWAYS debug your game before publishing to a game website here are a few bugs I noticed you can't climb slops and you constantly fall down steps and it seems like there are invisible blocks getting in my way all the time but if you debug it it could be really good!!
AHH I don't understand it's like sometimes I can move and sometimes i can't move in some directions and somethimes i can't even click myself AHHH i freaking out I die in like 2 turns 1 for me and 1 for the computer and my king is somehow dead Thats what i get for playing the most complexe and impossible game ever invented... CHESS!!!!!!!!!!!
It's not a good game you should search how to make a platform game on the web and think of an idea to turn it into a platform game and it was WAY to SHORT so make it longer!!
1/5 because i think the goal of a game designer is to make a game that challenges the player but isn't impossible see my advice would be to lower the gravity more each time you level up thus allowing you to jump higher and run faster.
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