Asclepius

He's a hero of Greek myth who studied under Chiron and he was a member of the Argonauts led by Jason. Being a child of Apollo, he eventually gained the power to resurrect the dead.

In Fate/Grand Order:

Asclepius serves as a Lokapala of God Arjuna.

In Fate/strange fake:

Asclepius is one of seven individuals manifested as Watcher's Shadows. He has the appearance of a young boy in his early teens.