NOTE: It isn't a system fic, I have just made a status of him in this auxiliary chap to give you idea of his abilities.
Name: Natsuki Subaru
Title: Satella's beloved, Envy's Daddy, The Great Sage of Old times, The New Great Sage, Aura King, Ki Martial artist, Psychic, Yandere Sword Saint's hubby.
Strength: 92 tons(Base), 1000 tons with(Magic), 10,000 tons with (Magic&Ki), 12,000 tons with (Magic, Ki and Aura)
Speed: 24 times the sound(Base), 30 times(Magic), 50 times(Ki/Magic), 60 times (Ki/Magic/Aura)
Mana: 1 million times greater than Subaru.
Icons: None
Divine Blessings: None
Authorities:
1) Sloth: Invisible Providence: The user can create 64 invisible hands sprouting from back or front, they are invisible and can exert strength around a few tons individually, and can phase through matter.
2) Greed: ???
Abilities:
1) Magic:
Natsuki Subaru has Yin and Earth Magic affinity, he can use all types of the Magic of said system available in Re Zero world.
2) Swordmanship:
Only likes of Julius surpass him in swordmanship.
3)Spirit Arts:
Subaru has contracted six spirits, out of which five are True Spirits, one is Great Spirit.
4) Ki:
Subaru can only use Ki to strengthen his Physical abilities and diffuse them as a destructive energy.
5) Aura:
Subaru can use Aura to sense everything in 360 degree within a hundred meters radius, he can sense hostility, shape aura to form constructs, or even exert them as a destructive energy, he can also interact with Astral plane and spiritual lifeforms with it.
6) Psychic:
Subaru can read anyone minds, use telepathy and teleport.
7) The Yin Sword:
Using Yin Sword Subaru can cut through time-space itself, the terrifying aspect of this ability is as long as Subaru can fix upon a target, he can slash it whether from past or future, or even in a different universe.
8) The Life Sword:
No abilities other than its know ability to destroy souls is explored.