I'm probably really late on this, but I JUST NOW realized that there are no more mwars, and is there a reason why?
The developers noticed that the overwhelming majority of system wars were MWARs. They decided to remove mithril payouts from system wars to nerf that possibility. This also made mithril gained from Estoc Edge Wars more popular since it is the only viable method of getting mithril (without buying it in the Alchemist). The devs kept system wars around because clans could still entertain the idea of having training wars... or if they wanted to do an old-fashioned system war.