What makes Codenames: Critical Role Adventures so special?

About Codenames: Critical Role Adventures, from BoardGameGeek:

Enter the world of Exandria, a land of infinite wonder and unexpected champions, and experience the Critical Role adventures through Codenames. Assemble a party of heroes from the first three Critical Role campaigns, embark on missions, and level up your characters to defeat the final boss. Codenames: Critical Role Adventures is a unique take on Codenames inspired by the Critical Role universe. It's a fully cooperative version of the game where one GM (game master) leads their party through perilous missions, each with its own twist and take on the classic Codenames rules and featuring a new set of themed words. Play the game in three separate campaigns, choose from seven Critical Role characters, and, by levelling them up, unlock new abilities and equip items to use during missions.