Captains/Warcheifs are infinite. New orcs will spawn into Captains, and can climb the ranks as well into Warcheifs.
Feud/other red missions are just side stuff - it's up to you. Sometimes it helps other Captains rank up if it's a 1v1 between Uruks, if you don't kill both Uruks facing off.
Feud/other red missions are just side stuff - it's up to you. Sometimes it helps other Captains rank up if it's a 1v1 between Uruks, if you don't kill both Uruks facing off.