There’s a book of knowledge in Sancta Helena’s Church of Essexe in Assassin’s Creed Valhalla. It’s within the city of Colcestre.
This book will grant you the ability of Harpoon Impalement.
Here’s how you can get the book of knowledge in Sancta Helena’s Church in AC Valhalla.
To begin, get to the location shown in the map below, marked by the book’s symbol.
How to get the book of knowledge
Head to Sancta Helena’s Church.
To enter the church, you can go through the side.
Move the shelf away and break the window to enter.
Collect the key first.
Now, head to the church’s main area and you can unlock the door with the key.
You will then need to climb all the way up.
Move the shelf and place it under the ladder. Use it to go up the ladder.
Then, shoot the link on the higher ladder to get it down.
Make your way up and collect the book to get the Harpoon Impalement ability.