Overwatch has recently added the Workshop modding tools, and while they don't allow players to create brand new maps, tweaking pretty much everything else is well within the realm of possibility. As you might imagine, this has quickly given rise to a whole bunch of new game modes, the most popular of which in NA/EU regions is apparently an adaptation of the Uno card game!

If you're wondering what other crazy modes people are currently playing, as well as which ones to check out yourself, you might be glad to hear that Blizzard has now released a list of the most popular custom games per region. Needless to say, there's some pretty good stuff in there!

I wouldn't exactly recommend playing Uno as that tends to be somewhat boring even when you have friends around, but I would highly recommend you check out "Floor Is Lava Parkour". Not only is it a well designed mode with an interesting set of tasks, but it's actually fairly challenging and extremely satisfying to master. It'll probably make you want to tear your hair out at some point, but on the positive side, it will also make you intimately familiar with some of the movement mechanics.

As for the Korean modes, apparently "High Blood Pressure Marathon" is really, really, really fun if you like messing around with other people and don't mind them returning the favor. I haven't tried it myself so I can't exactly go into detail about it, but given that it's currently the most popular game mode by a large margin, I would say it's well worth looking into. 

Have fun exploring all of the new game modes!