These guys are the last heroes still fighting for the so-called Remnant Factions, the once-mighty civilizations left broken ever since the titular Sorcerer King smashed their armies and cities into tiny pieces many years before the game itself begins.
"Their loyalty can be yours, but at a price: you'll have to help their people by completing unique quests before the Remnant Factions and their Champions will throw in with you for one final gasp of defiance against the evil Sorcerer King's dark reign. Korthox the Ice Lord, Esperaza the Avenger, and more will prove capable allies if you can earn their trust through battle and sacrifice," explains
And let's face it, you want someone called Korthox the Ice Lordon on YOUR side, rather than the other guy's, especially because judging by an accompanyinghe appears to be a frost giant riding an ice spider. To get a Champion on your team you'll have to complete a unique chain of quests, so you'll be glad to know that another change Stardock highlights in the patch notes is an overhaul of the quest system itself, with "more, better rewards and additional multi-step quests." You'll also find enhanced end-game stats to help you pin down where you where going right or (more likely) wrong.
You can find the full list of.