Not the healthiest of hobbies but I stumbled into DOTA (the league of legends precursor) 20 years ago and have never fallen out of love.

It's been a dangerous addiction at several points of my life, but in many ways has revealed to me more insight about myself than any other activity.

There is so much variation and nuance, there's always something to learn. For a naturally curious and slightly competitive person, it's quite an intoxicating cocktail.