Very nice puzzle game that lets you figure the rules out on your own and really tests you with counterproductive elements in :) Some suggestions though:
-Since a wrong step may ruin the whole setup requiring a restart, it may start getting a bit frustrating and feel like a trial-and-error. Possibly a key to save a particular position may be considered?
-Those who aren't too familiar with the colour scheme (e.g. me) may need some help in intuitively comprehending colour combinations. A possible way to fix this may be to change the portal at the end to the colour wheel?
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