The Grim Reaper

Upon the destruction of The Underworld in 2031, at Spartan's hand, the Grim Reaper was set loose onto the world. As opposed to the Reaper's usual job as a Warden of Hell and the Soulbringer, he now wandered the world aimlessly, hoping to find meaning in life.

Soulbringer
In his Soulbringer days, The Reaper brought souls who miraculously evaded both death and Destiny itself at the same time, however, that happened rarely. The Grim Reaper was best known on Earth for leading lost souls to the afterlife, however in truth, that was not how he spent most of his days.

In Hell, the Grim Reaper was better known as the Warden. He was the overseer of Hell, leading every single demon and watching over every single soul in the Underworld.

Reapers
In the past, when Destiny was less strict and evading death was more common, there were several Reapers. But as time passed, and Destiny got stricter and stricter, bringing death into his own hands, The Reapers all died out but one.

Abilities
Reapers have many abilities which make them a powerful foe, in combination with their actual skill, for any mortal man; fighting a Reaper is a death wish.

Reapers possess a healing factor that exceeds any other in hell, only second to Lucifer's. However, unlike Lucifer's, a Reaper's healing factor doesn't weaken when out of the Underworld, which makes Reapers far more formidable foes.

A Reaper also possesses enhanced strength, matching that of Lucifer's.

Reapers can also seek out lost souls, making it impossible to hide from them.

They can generate portals to get them in and out of hell, along with anywhere else in the universe.

Reapers also have a special property of being able to kill anything from Hell without it simply waking up in back Hell, hence, them being the Wardens of hell.

'''If killed, Reapers simply wake up back in hell. They are virtually impossible to kill.'''

Only Lucifer can remove their immortality.

Skills
Every Reaper is trained in using a Scythe, their main weapon, however, they can easily adapt to any other weapon and only started using scythes because Lucifer was amused by human's depictions of Reapers.

Reapers are skilled in hand-to-hand combat, incredibly smart and can preconstruct and predict movements in their mind.

Reapers also have a vast library of knowledge that includes every object in the universe, in combination with their superior intellect, Reapers are also excelent detectives if needed.

Their vast library of knowledge also includes every language in the universe.