Alt accounts are allowed on ManaCube and have many purposes. They are mainly used to AFK mob grinders to generate income. Since spawners only work when the chunk is loaded, alts are able to load multiple chunks and plots to allocate money towards one main player. Alts must be within 15 blocks of the spawner for mob grinders.
AFK machines and console clients to have alts automatically rejoin the server after a reboot are allowed. The alt limit is ten accounts per IP, including your main account. Any means to bypass the alt limit are not allowed, which include but are not limited to:
/cow) You can only claim these one time rewards on the 10 accounts which you are allowed to connect.
WARNING: Any attempt to bypass and twist alt limit rules will not be pre-approved by staff, and may result in a ban from leaderboards, payouts, and a local ban from the realm.