10 Video Game Bosses Who Can Secretly Join Your Team
9. Sarevok Anchev - Baldur's Gate II

Sarevok Anchev is the main antagonist of the original Baldur's Gate. Known as the Deathbringer, he is the son of the dreaded god of murder, Bhaal, and his goal is to dominate the world in his father's name.
Well, this is Sarevok in Baldur's Gate 1, at least. In Baldur's Gate 2, on the other hand, Sarevok can become your adorable little paladin buddy.
You see, despite being canonically killed in the original story, Sarevok makes a surprising reappearance in the sequel as a recruitable companion.
Your wary partnership begins when his spirit offers to help you track down the new villain in exchange for resurrecting him in a new body. It may not sound like the smartest idea, but surprisingly, after Sarevok comes back to life, his first instinct isn't to slaughter the innocent and conquer the world.
Depending on how you treat him, Sarevok can actually overcome his unholy craving for violence and become a rehabilitated man, committed to protecting the world under a paladin's oath.
Alternatively, you can reenable his old urges and become menaces together, but either way, you and Sarevok get to stay best friends forever.