Fate/stay night: eternal oath

You are Shirou's adoptive brother who also survived the great fire. Note: I do not own this image.

The 8th Servant (Fate UBW x Male Reader)

When a mysterious 8th servant appears in the Holy Grail War, something that shouldn't be possible, things are bound to change. What will happen to y/n and how will he affect the story? Read to find out. I don't own anything.

Fate's Blacksmith

The reader is a Castor class, who is also a blacksmith. He is immortal and has a sort of clairvoyance that he calls his "Foresight". He doesn't know what will happen, but he knows where he needs to be. With this, he has forged the greatest weapons from Hercules' blade to once fixing the legendary sword Excalibur. Now...