The Four Sinistrals

The Abyss Lords are the main villains from Romancing SaGa 3.

Story
The Abyss Lords are the rulers of the Abyss, a dimension where the demons dwell. About 600 years ago, the Death Eclipse (an event that hits the world every 300 years, killing all newborn life on the planet) hit the world. A single child survived, inheriting awesome magical powers and become the Devil King, ruling the world with an iron fist. The Devil King then opened the Abyss gates, allowing the Abyss Lords into our world to serve him. However, one day the Devil King vanished, leaving the Abyss Lords to rule our world as they pleased. Around 300 years ago, the Death eclipse hit the world again, and again a single child survived. This child became the Holy King, and supported by powerful weapons and allies he banished the Abyss Lords back to the Abyss.

15 years ago the Death Eclipse hit the world once again, and it's power reopened the Abyss Gates. The gates, however, were too small for the Abyss Lords to go through, so they sent clones of themselves to try and capture the new destined child, so that they could fully open the gates and enter our world again. The clones are destroyed by the heroes and the four gates are closed. However, as they closed the last gate, Sarah, one of the two destined child, enters the Abyss in order to sacrifice herself to let the world live in peace until the next eclipse. The heroes, along with Shonen, the other destined child, discover that there was still one Abyss Gate left, so they go after it in order to destroy the Abyss Lords and save Sarah. The true Abyss Lords are finally defeated one by one, leaving the heroes to face the Destroyer in order to save Sarah and the world.