The height (y-axis) is time and each turn alternation your row moves one down and through capturing the pieces, one can make changes to history and therefor prevent others from beeing captured. Btw. checkmating is not implemented yet, so just capture the king, and you won, but who needs winning screens anyways.

Since this is just a prototype, here are a few TODOs:

Rewrite project in a functional clean style (because now, it's a real mess)
Adding closer time history tracking, for example the grandfather paradoxon
Add win condition and check mating
Add time loop, when last row is reached
Fixing additional bugs
Adding simple minmax-opponent