Sometimes a unit will be almost entirely wiped out, with only a single member left. Such lone individuals must take a Leadership test at the start of each of their turns. If they pass, they are filled with heroic fervour and continue to fight on single-handedly. If they fail, they suffer an outbreak of common sense and begin to fall back.
All On Your Own (Last Man Standing)
Source: 3rd-A-Palooza (3.5) Rulebook v1.4, p. 29