Kerbal Space Program, my one true love.

I've got a few games with 100-300 hours of playtime, but KSP is EASILY in the thousands, I wouldn't be surprised if I'm over 10,000.

And before you ask, no, I'm not an expert, most of my rockets are named either "1.4.2.A.1(b)[rev. 5.0]" or "bendy fuckstick 9000 (mun)"