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Blaz and Asterion Ouroboros + Class (Xenoblade 3)

Asterion: Juggernaut
The Tank, Wield Greatsword, Greataxe, and Fist weapons, Juggernaut sustain a lot of damage in exchange, allowing the said damage to become as "energy" to the weapon
Ultimate Art: Vermillion Jupiter
Chain Art: Thunder Reign
Ouroboros Art: Horizon Thunder
Passive skill: iron Skin -  Damage reduction by 10% and gained invincibility once entering berserk state. And Systematic Emergency, When fallen, revives back to 100% but once per battle

Blaz: Ruin Sage:
The Damage Dealer, Using Sigils, Gylphs, Ether, and Pages. The Ruin Sage calls forth the ancient "Blades", Destined to no longer rule the aionios, But they lived on as Legends and stories. 
Ultimate Art: Apocalypse (Wulfric LVL 4)
Chain Art: Maelstrom of Darkness (Dromarch LVL 4)
Ouroboros Art: Blade Legacy (Perceval, Boreas, Corvin, Ursula, And Sheba) 
Passive: Ether Burn / Soul Burn : When blaz gets damaged, the ether/soul burn will happen and it will periodically bounce to one target to a another, dealing heavy damage. And Mirror barrier, Reflection + Thorn damage to enemy, but risking taking damage from any side, however with ether / soul burn, it was a compliment and passive combo

Ouroboros form : The Juggernaut and the Sage 
Asterion ouroboros form does resemble behemoth from Final Fantasy but more bull like and his horns have the rings floating, it's ouroboros weapon is the Greataxe.
Blaz ouroboros form is more bulkier with it having a circular ring as replacement of it's legs, aura of ether flows as strings and it's ouroboros weapon is sigil of ruin
The Common aspect of both are the rings, Asterion has the rings on his horns and his greataxe while blaz has circular ring leg that made him float along with smaller rings that floats around the ether strings. and the second was the element, Asterion has the lightning shaped marking on the ouroboros face while blaz has the elemental tree on his chest.