The captive grephs have been bred over the years into fighting creatures known as dragons, ranging from the man-sized "Termagant" to the gigantic "Jugger". As each new variety has been bred over the years, the fortunes of war have shifted between the Banbecks and the Carcolos.
Over generations, captive grephs have been selectively bred into various dragon varieties, from the small "Termagant" to the enormous "Jugger".  The outcome of battles between the Banbecks and the Carcolos has fluctuated with each new dragon type introduced.