Like his father and uncle, he is a Venus Adept
As the son of the previous games' Isaac and Jenna, he looks very identical to his father when Isaac was 16, and wears the same yellow scarf as his father, which was apparently passed down to him.
When meeting Briggs, he comments that Matthew has inherited Jenna's spirit and her eyes. When Himi joins the party and you visit Uzume's tomb in Yamata, using Spirit Sense on the Dancing Idol will cause Uzume to recognise Matthew as Jenna's son.
(For this i use watercolor brushes n-2 and 16 )
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