During 2012 World Championship, CloudTemplar used a lot of nasty swearword while he chasing Jarvan IV played by illuSioN in teamfight, and observer accidentally shown their whole conversation in public. Because his swearword was North Korean dialect, he gained nickname of Buk-tem, or "Northern templar". He later mentioned they said nasty things freely because Riot promised they will not broadcast any team conversation, but they did.
His swearwords wasn't a North Korean dialect. One of the swearword he used, '간나'(Ganna) is term for North Korean Spy. He has perfect South Korean dialect.