FYI - max stack size = the sum of that red number on the counter's right hand side *for all leaders* in the stack. Spartacus has two lieutenants, and their total stack limit is 16, add themselves and the PC marker "under" the stack for a grand total of up to 20 units here.
In actuality, he had 12 combat units in his stack ... what can I say, there were a lot of slaves in ancient Rome.
