DO NOT CLEAN CARTRIDGES WITH WATER.
Use isopropyl alcohol, preferably 90% or greater (the percentage is how much is alcohol vs how much is water) because it evaporates quickest, dip a q-tip in the alcohol, squeeze out the excess from the q-tip (you don't want too much), and clean the contacts...
I would absolutely not be surprised if the fact that the SNES version wasn't released on cartridge in Japan has something to do with it. Like IDK 'not wanting Japanese players to be mad because North America and Europe get the SNES version of this game and Japan gets the NES version' just feels...
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▄░▐░░░▄▄░█░▀▀ U HAVE BEEN SPOOKED BY THE
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░░░░░░▐▌▀▄▀▄▀▐▄SPOOKY SKILENTON
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the answer to the question of 'is the switch an 8th generation console or a 9th generation console?' is 'whichever option makes you mad and causes the most arguments'