Zeldris

is an elite warrior of the Demon Clan, serving directly under the Demon King as a member of the Ten Commandments.

Appearance
Zeldris greatly resembles Meliodas, though his hair is black and grows counterclockwise to Meliodas'. They have the same demon markings, though Zeldris' is over his left eye instead of his right.

He his clothes are crimson in color and have an insignia (presumably representing the Demon Clan) on several places. He has silver gauntlets and carries his sword by a strap on his hip.

Personality
Zeldris is very calm and collective, seemingly not easy to anger. Like his brother, Meliodas, Zeldris appears to have good commanding and leadership skills.

Despite being a demon and seemingly evil by nature, Zeldris does seem to have a somewhat caring side, 3,000 years ago when tasked with executing the vampire clan for their planned betrayal he instead chose to seal them instead of kill them all. All for Gelda's sake, showing he may have cared for her.

Zeldris is confident in his abilities. Clashing with his own brother Meliodas in the past, a very powerful opponent and remain unfazed about the prospect of doing so again and even initiating an attack against him. He also seems to be unwilling to negotiate with Meliodas despite being brothers and seems to hold a grudge against Meliodas, being labelled as a traitor among Zeldris and his fellow Ten Commandments.

In his own words, the only things left for him are rage towards Meliodas and a desire for vengeance against the other four races.

3,000 years ago
During the great war, Zeldris was tasked with executing a clan of vampires who attempted to overthrow the Demon King. However, instead of killing them, he sealed them away for Gelda's sake. Sometime in the past Zeldris clashed with his brother Meliodas. Along with the rest of the Demon Clan, Zeldris was sealed away by the Goddess Clan after losing the Ancient War against the Four Races (Human, Fairy, Giant and Goddess Clans).

Albion arc
After Hendrickson managed to remove the seal, Zeldris and the rest of the Ten Commandments appeared before the terrified former Great Holy Knight and Fraudrin in Dreyfus' body with Zeldris uttered Meliodas' name as if he knew him. After being informed by Fraudrin of the current events in Britannia, Zeldris suggested that they should head for Edinburgh Hill for recuperation of their severely drained magical powers due to the seal they're trapped in, which everyone agreed and left Zhuhur Valley by flight, leaving a terrified Hendrickson.

Arriving at Edinburgh Hill, Zeldris and his fellow Ten Commandments find a castle in ruins and concludes that it was Meliodas who caused the destruction of the castle as if there was a great battle fought there before noticing his brother Estarossa in a laid-back self, relaxing in the castle's ruins much to Zeldris' chagrin. Later on, the Commandments continued to rest and recover their magical power through the souls of humans they devoured and were shocked when they sensed Meliodas regain his full Demon powers at Istar.

Istar arc
Suddenly, Meliodas appeared out of nowhere through Merlin's teleportation and casually greeted the Ten Commandments who were alarmed of his sudden presence, Galan who was determined to finish off where he started. 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. 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". Afterword, Zeldris suggest the Ten Commandments to split up and move across the land to regain their magic faster while calming Galan down after his lose against Meliodas. However, Zeldris remain behind as Estarossa refuse to move as he want to relax after being sealed for so long while Zeldris decided to look around.

Abilities/Equipment
Like all members of the Demon Clan, Zeldris utilizes the mysterious jet-black power of darkness for a variety of purposes such as forming wings to fly.

As a member of the Ten Commandments, he is exceptionally powerful. His aura is so powerful that he made the normally calm Hendrickson sweat in fear of his presence, combined with the other Ten Commandments. He apparently fought his brother, Meliodas, in the past, who is legendary for his strength, and shows no fear or hesitation at the prospect of doing so again.

Immense Speed: Zeldris has shown himself to be an incredibly fast individual, able to descend from the height of Edinburgh castle to perform an attack on Meliodas in less than a second to attempt to prevent his escape, appearing as nothing more than a blur while he did so.

Weapons
Zeldris wields a shortsword that lacks a sharp point on the end and instead is curved all the way round.

Meliodas
The relationship between the two as it is now is one of hostility. Zeldris seems to harbor nothing but anger towards his traitorous brother. The exact details of their relationship 3,000 years ago before is unclear but he seems to be unforgiving of Meliodas' actions, whatever they may be, in the present day.

Estarossa
Both of them are Commandments, though Zeldris seems occasionally exasperated with Estarossa's lazy demeanor he does seem to respect him, as his older brother.

Galan
Zeldris seems to hold Galan in contempt, viewing the older demon's pride as symbolic of why the Ten Commandments were humiliated and sealed in the war. When Galan urges Merascylla to locate Meliodas after he "greets" them Zeldris simply replies that, Galan as he was then, would merely be defeated again and that he should "cool [his] little head."

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Zeldris