Ever as Fate Must

To find Grendel’s lair, follow the trail of mould heading southwest of Brisleah Farm. Use Odin’s Sight to track the mould down a dirt path towards an abandoned mine pit.

Head down into the pit. It is a dark area, so light a torch by holding 'T' to see.

Follow the pathway through the tunnel until you reach a cavern.

Hop onto the wooden post and then over to the next platform to go through the door on the left.

Continue through the tunnel system, parkouring across narrow stone ledges.

Use the wooden structures to hop up onto a wooden platform that leads to a new tunnel.

As you proceed, your vision will blur more intensely. At the end of the tunnel, climb the wooden structure to a higher ledge and continue onwards.

A couple of snakes will attack you in this tunnel; defeat them with a melee weapon or your bow.

Jump down into an even deeper pit, marked as a Cursed Area. It is extremely dark and your vision will be very blurred.

Use Odin’s Sight to locate the key to unlock the door, found to the west on a stone block.

Behind the locked door, you will find Grendel’s Mother. She can be defeated with a few arrows to the head before she reaches you.

After defeating Grendel's Mother, you will discover she is an old woman protecting her son.

To clear the Cursed Symbol, follow a narrow tunnel heading south out of the cave room.

Move the large object out of the way to reach the next section of the cave.

Head up the wooden structure in the cavern, then back down the pit to find the Cursed Symbol.

Make your way back through the cave towards the church where you found Hrothgar.

Speak to Wulfhilda at Brisleah Farm and tell her of your discoveries.