Will from The Amber Spyglass is a strong secondary character is this novel (The Amber Spyglass). He came to Lyra's dimension/world with the use of a device called The Subtle knife. It literally cuts a hole through the dimensions. He is able to cross between them. He lost several fingers on his hand when he struggled with someone over the knife in the second book. His love for his mother and for those close to him is his greatest strength and it assists him in making some very hard decisions. He is brave and does not hesitate to follow Lyra into the land of the dead.