SEGA and Three Rings announced today that Spiral Knights has grown to one million player accounts worldwide. To celebrate, the Ironclaw Munitions Factory dungeon (seen above) has been added to the game.

Last month, Spiral Knights became one of the first free-to-play games available on Steam. For more details on this hack 'n' slash dungeon crawler, watch Mike B. aka Fony's recent BFF Report and check out Senior Staff Writer Chris "Pwyff" Tom's impressions.