2.8 The user account is not transferable without the explicit consent of Gameforge. The submission of the approval by e-mail is sufficient to fulfil the written form requirement.
from here:
http://agbserver.frogster-online.com/enG…s-of-Magic.html
So unless you have a written consent
previous to handing the account over to another user, it is forbidden. And absolutely no real money trade is allowed to be involved, so you can not sell an account for real money:
7.4 The user may under no circumstances
(...)
c) use virtual objects used in the online games outside of online games,
buy or sell them for "real" money, swap them or cause such activities.