The Bolt of Gransax is one of the legendary armaments you can find in the Lands Between. This almighty weapon has the ability to become a powerful lightning bolt that can be thrown at your opponents. There is no doubt that you should get your hands on this weapon if you plan on using a dexterity build. Here is where you can find the Bolt of Gransax in Elden Ring.
To obtain this spear, you first need to get into the capital city of Leyndell. To do this, you can need to obtain at least two of the Great Runes that can be obtained before venturing into the city. You get Great Runes from defeating Radahn, Godrick, and Rykard. After you have the necessary number of Great Runes, defeat the Draconic Tree Sentinel that is blocking the path into the capital city and you will have access.
Once inside the city, follow the paths and make your way to the giant dragon statue. You can climb the wing of the statue. Do that to reach the West Ramparts Site of Grace. From there, use the tree roots to reach the boss arena where you will fight a spirit version of Godfrey. After the boss fight, exit the arena using the elevator. At the bottom of the elevator, follow the path and keep on the lookout for an area to jump over the railing and onto a spear that is connected to the dragon statue. The area to jump off is near a Crucible Knight. Climb the spear and you will find the Bolt of Gransax a little way up.
Keep in mind that you need to obtain this spear before you complete the Crumbling Farum Azula. If you complete that area, the spear will become unobtainable thanks to changes that happen to the capital city. This will also prevent you from being able to get the achievement for the legendary armaments.