rioter vs troublemaker

rioter and troublemaker both are nouns.

Word	Noun	Adjective	Verb	Adverb
rioter	Yes	No	No	No
troublemaker	Yes	No	No	No

As nouns, troublemaker is a hypernym of rioter; that is, troublemaker is a word with a broader meaning than rioter:

rioter: troublemaker who participates in a violent disturbance of the peace; someone who rises up against the constituted authority
troublemaker: someone who deliberately stirs up trouble

Other hypernyms of rioter include bad hat, mischief-maker, trouble maker, troubler.

rioter (noun)	troublemaker (noun)
troublemaker who participates in a violent disturbance of the peace; someone who rises up against the constituted authority	someone who deliberately stirs up trouble