Here is the full list of all 21 Black River achievements.
Exit the village alive.
Release Thorne from his enslavement.
Summon Hallvorn.
Witness Calisto breaking the last seal.
Save Matthias from the zombies.
Meet the Deformity.
Collect all of Ivy's diary pages.
Find Leah at the Mansion.
Get Ira and Bardra to work together.
Use him to open the gate.
Thorne is here!
Meet the Crawler.
Be the meal of their party.
Just stare at it.
Get caught by Bobby.
Defeat Blondie.
Open the Treasure Chest while being chased by Bobby.
Rescue all survivors at the Bone Pit.
Get ambushed by the Deformity.
Kick his ass.
Save the villager from the zombies.