I am reborn, from the realm of chaos. Through all the time that has passed, my hatred has raged on! All living things on this earth will be burned by the flames of Hell!
~ Arem

Arem is the final boss in the non-canon game Ys IV: The Dawn of Ys.

Referred as the original leader of the Clan of Darkness, Arem had conquered the land of Celceta in the past using his military might, plunging the land into a age of darkness, which earned him the title of "Lord of Slaughter". The hero Lefance, along with his five disciples fought against Arem's forces and eventually killed him in battle.

In this version of the game, Gruda's schemes revolve around using the power of the Mask of the Sun to revive Arem, which he accomplishes after he backstabs and kills Eldeel. The hero Adol fights Arem at the center of the Temple of the Sun, where he ends defeated for good.

Ys Villains

Ys Origin and Ancient Ys Vanished
Epona - Kishgal - Zava - Dark Fact - Dalles - Darm
Ys III: Wanderers From Ys and The Oath in Felghana
Dularn - Chester Stoddart - Count McGuire - Nikolas Garland - Galbalan
Ys IV: Mask of the Sun, Dawn of Ys and Memories of Celceta
Romun Empire - Commander Leo - Bami - Gadis - Eldeel - Gruda - Arem
Ys V: Lost Kefin, Kingdom of Sand
Dorman - Ibur Gang - Karion - Baruk - Abyss - Rizze - Jabir
Ys VI: The Ark of Napishtim
Jue - Xisa - Sera - Admiral Agares - Ernst
Scias - Tialuna Rem Iskalia - Rul-Ende