The Tempel brewery and the festival Mörkaste Småland had a collaboration in 2016 where an official beer was brewed for the festival. This shirt was worn by the representatives of the brewery. And since I enjoy their beers and the festival, I couldn't pass on this one.
(The last picture is borrowed from the brewery/festivals' facebook page. If anybody affiliated thinks it shouldn't be here for any reason just let me know and I'll take it down)