Here is the full list of all 46 Sorcerer King: Rivals achievements.
Defeat a Minor Faction that has sided with the Sorcerer King
Slay Aegethon
Play for 5 hours
Complete the Campaign
Win a game without a single shard destroyed
Win as the Wizard
Achieve Ascension Victory
Settle a new city
Complete a Champion Quest to recruit a new Champion to your cause
Reach level 15 with a champion
Ally with a Minor Faction
Use pioneers to upgrade an Outpost
Lower the Doomsday Counter
Get a city to level 9
Equip a champion with items in every slot
Channel the focus of your Magic between Mana, Lore, and Sovereign Skill
Get a city to level 5
Reach level 5 with a champion
Use a pioneer to build an Outpost
Win a tactical battle
Use the Sovereign's magic to intervene in a tactical battle
Craft an item
Build your first city improvement
Claim a Shard
Complete a Quest
Play for 15 hours
Play for 40 hours
Play for 100 hours
Found 5 additional cities in a single game
Slay Vetrar
Destroy one of the Sorcerer King's Strongholds
Kill an enemy with a pioneer attack
Win a "predicted defeat" tactical battle
Win a "predicted defeat" tactical battle without taking damage
Win 20 "predicted defeat" tactical battles without taking damage
Win a game on Insane Difficulty
Win as the Guardian
Win as the Tyrant
Win as the Priest
Win as the Tinkerer
Win as the Commander
Win as Undead
Win as Frozen Realm
Defeat Nabunihr
Defeat Abeix
Defeat Corvos