Originally Posted by
Ethien
The balance of having an unroutable army could be compromised with slower movement, lower defenses and so forth. I don't expect anything but elite units from the undead to be comparable to the elite units of other factions. Also if the Tomb Kings are unable to ally any other faction (as it should be) then that would also help balance the incapability of their undead units to route.
My latter suggestion would make it workable to have locked_morale units balanced. When you are against every other living faction, then you'll need some sort of boon.
Edit:
@King - Oh no, it's illegal even if it's for free. You cannot do that legally and any such modification cannot be posted on these forums. This has been done through other mods and they were banned from here.