It started with the good old THE HARDEST VIDEO GAME BOSS EVER (https://www.youtube.com/watch?v=sQZuidKexBQ), and I'm pretty sure the related videos took me to Dracil's IN Extra clear (https://www.youtube.com/watch?v=4Nb5Ohbt1Sg). At the time I thought these were all arcade-only games, so I left them alone for a long time.
In 2012, I saw a friend playing IN, and I recognized it from the videos I had seen years ago. The rest is history documented in my signature below haha
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