You will get Grafted Blade Greatsword and Banished Knight’s Halberd by doing Irina’s Questline in Weeping Penisula. This guide shows the complete questline of Irina in Elden Ring.
Irina’s Location to start the quest
You will find Irina south of the Bridge of Sacrifice in Weeping Peninsula at the location shown in the pictures below. She will give you a letter and ask you to deliver it to her father in Castle Morne.
Deliver Irina’s Letter to her Father in Castle Morne
Irina’s Father is in Castle Morne, which is on the southern side of the Weeping Peninsula as shown in the pictures below.
Enter the castle through the main gate and go straight. Turn right when the path ends as shown below. After turning right, go straight ahead and climb up the ladder at the end of the path as shown in the second picture below.
Then turn right and go straight ahead. Turn left at the location shown below.
Jump down here and go straight ahead. Then climb up the stairs to reach the roof of the tower as shown in the pictures below. You will find Irina’s father on the roof.
Defeat Leonine Misbegotten Boss
After talking to Irina’s father, go south of Castle Morne and defeat the area boss (Leonine Misbegotten) as shown in the pictures below. It will drop Grafted Blade Greatsword.
Report back to Irina’s father Edgar
Report back to Edgar, and he will tell you that now he will go back to his daughter, Irina. You can Kill Edgar now and take Banished Knight’s Halberd from him. Or you can continue the quest and get it later.
Go back to Irina’s Location
Go back to Irina’s Location south of the Bridge of Sacrifice. Here you will see that Irina is dead and Edgar will be weeping near her corpse.
Face Edgar the Revenger
Go to Revenger’s Shack in Liurnia at the location shown in the pictures below.
Rest on the Site of Grace at the Revenger’s Shack. Shortly, you will be attacked here by Edgar the Revenger. Defeat him to complete the questline. He will drop Banished Knight’s Halberd.
