Trackmania: Nations Forever is a free racing game, and if you work on White%, it will take you less than 10 minutes per run, with the WR being 5 minutes RTA.

Any run related to Hearthstone. It took me like 30 attempts because it's an "all or nothing" run, where you can't save, and you have to beat the whole run right there and then, and with some runs lasting 30 minutes before you have to reset, I was happy to get where I am now.

But now I plan to do Trackmania: Nations Forever, where there's not really run resets, just in-game resets.