Nidhogg is here. The insanely fast indie dueling video game has arrived on Steam, over three years after it began winning accolades from the gaming press. Originally only playable at video game exhibitions where crowds would cheer as a pair of players faced off in the epic tug-of-war-like sword-fighting game, its creator Mark Messhof Essen is finally selling Nidhogg to the masses, complete with online multiplayer. For $14.99 (or $11. …