An MMO called Mabinogi, but only because it’s literally designed to suck as much time and money away from you as possible without you noticing. Steam says I’m nearing 5,000 hours, but more than half my playtime was from before it was on steam, so it’s probably closer to 12,000 to 13,000 hours. I haven’t even reached the end game yet.
At this point, I don’t really play it anymore. I think from now on I need to start avoiding games that are gonna absorb that much of my time for so little progress. Definitely wasn’t mentally healthy because I wasn’t even enjoying myself a good way in, I was just addicted.