(Spiral Knights is copyright Three Rings Design.)
I became interested in the Troika swords after seeing their attack animation in person. It’s a beautifully executed pirouette most of the time, one of high damage dealt in a nearly 180º arc.
Plus, the developers seem to like word play puns. Troika is a Russian folk dance, and Khorovod is a Slavic art form involving dancing (and circle dancing at that).
I don’t know what Kamarin means.
ETA: nekobawt found the answer, which is totally keeping in theme. Neat!