Crossed Thanatos

Crossed Thanatos is a near-invincible monster summoned by Kilkapul. Its summoning required Kilkapul to sacrifice himself, his family, and his village. It is completely immune to both magical and physical attacks. It can split into more versions of itself when attacked.

Personality
Crossed Thanatos shows little to no personality, as it never said a word. Its sole objective was to kill Seiya.

History
After being summoned, Crossed Thanatos relentlessly chased down Seiya, even into the Divine Realm. It easily dispatched gods that got in its way. Having no other option, Seiya lead it to Valkyrie and gets it to destroy her painting, enraging her. It is defeated and never seen again once she used Valhalla's Gate to seal it away.