Here are some possible opposites depending on the context:
If "liege" means "sovereign":
* Subject: A person under the rule of a sovereign.
* Rebel: Someone who opposes or fights against the sovereign.
If "liege" means "loyal":
* Treacherous: Betraying trust, disloyal.
* Disloyal: Not faithful or committed.
If "liege" means "bound by duty":
* Free: Not bound by duty or obligation.
* Independent: Not subject to the control of others.
Ultimately, the best opposite for "liege" depends on the specific context in which you're using the word.