Ten Commandments

The are an extraordinarily powerful group of elite warriors, even among the Demon Clan, handpicked by the Demon King himself. Each member possesses a, a unique power gifted to them by the Demon King. This power is absolute; it cannot be opposed even by the Commandment who holds it.

Overview
Three thousand years ago, the Ten Commandments fought for their clan against the other four clans (Goddess, Human, Giant and Fairy) in the Ancient War but were defeated and sealed by the Coffin of Eternal Darkness but Fraudrin somehow managed to avoid being sealed and sought ways of releasing his people for centuries, until the present day, when he was able to manipulate Hendrickson into freeing the other nine members from the seal (as he did not have enough of Elizabeth's blood to break the seal completely).

Deciding to recuperate their lost magical powers drained by the Coffin, the Ten Commandments left for Edinburgh while leaving a terrified Hendrickson behind. Arriving at their location, they were surprised to see the Maiden Castle to be in a messed up state almost unrecognizable, unaware of Escanor behind the castle's current state and later a very deep hole caused by Meliodas, but rested there anyway.

Their presences in Britannia awoke two of the Demon Clan's Albion, one at Camelot and the other at the Fairy King's Forest, which were destroyed by Meliodas and King. Sensing the Albions' destruction, Galan was delighted to know that there are still powerful people even in the current age and decided to take action despite them still having yet to recover their full power. He traveled all the way to Camelot in 72 high jumps and encountered three members of the Seven Deadly Sins. He easily overwhelmed them and annihilated almost half a portion of Camelot and its citizens and slaughtered its Holy Knights in battle. However, Gowther's power Invasion deluded Galan about having killed Meliodas, Diane, Slader, and Merlin.

Later on, the Commandments continued to rest and recover their magical power through eating the souls of humans they devoured and were shocked when they sensed Meliodas regain his full Demon powers at Istar.

Suddenly, Meliodas appeared out of nowhere through Merlin's teleportation and casually greeted the Ten Commandments who were surprised by his sudden appearance. Zeldris and Fraudrin were going to attack him but Galan told all of them to stay out of it as Meliodas is his prey to kill. Melodias battled and defeated Galan in less than ten seconds before warning Zeldris that the Seven Deadly Sins will defeat the Ten Commandments with everything they've got, warning them of their doom if they stepped out of line.

In response, Zeldris and Fraudrin attempted to attack Meliodas from both sides, but he was teleported back to Istar. Galan was angered and humiliated by his defeat at the hands of the "Accursed Demon".

As Galan complains and commands for Merascylla to find Meliodas he is cut off by Zeldris as he tells him and the other demons that their goal is the domination of Britannia and commands the others to move out in groups of two (or more) in order to recover their magic power as quickly as possible and to use whatever methods they deemed necessary to eradicate the other four clans. Fraudrin then asks if this was a declaration of war against Meliodas which he reply's saying that this isn't war but an extermination.

Still angered by his defeat and the thought of Meliodas being 'beyond' him, Galan tries to clams to have been able to defeat Meliodas any time he wanted, however before he can finish his sentence he is stopped and warned about lying by the largest demon, questioning if he had forgotten that the Ten Commandments would incur their own 'curses' on themselves if they break their own laws. Galan then lowers his head in response but still curses Meliodas in his mind. The Ten Commandments then disperse, Zeldris and Estarossa, however, remain behind.