Rogier is one of the many NPCs you will come across on your journey and perhaps one of the most helpful. He sells you magical Ashes of War that allow you to make your weapons scale with intelligence. If you follow his questline properly, you will be gifted his rapier. Here is how you get Rogier’s Rapier in Elden Ring.
Rogier can first be found in Stormveil Castle near where you fight Godrick the Grafted. He is in a church on the path leading down from the Rampart Tower Site of Grace. Speak with him and he will tell you about Godrick and request that you defeat him. You can also find Rogier before this as a summon for the boss fight against Margit, though you don’t need to summon him to make him appear at the church.
After beating Godrick, head to Roundtable Hold. Once there, make your way out onto the balcony and look to the right. Rogier will sitting against the wall. It turns out he lost the use of his legs. Because of this, he can no longer fight. He will gift you his rapier for defeating Godrick. You receive it as a +8 weapon and it comes with the Glintblade Phalanx Ash of War on it that summons homing missiles around you.
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