Tecrod
Tecrod, the Hated Slave, is a member of the Lightless, a race of beings that serve as the main antagonists of the Abyss Challenge League. No official depiction exists of him.
Lore
Little is known about Tecrod, as they are only ever referred to in the flavour text of the unique abyss jewel 
Tecrod's GazeTecrod's Gaze
Murderous Eye JewelAbyssRequires Level 40+(10-20) to Strength
40% increased Main Hand Critical Strike Chance per
Murderous Eye Jewel affecting you, up to a maximum of 200%
+20% to Off Hand Critical Strike Multiplier per
Murderous Eye Jewel affecting you, up to a maximum of +100%The Hated Slave seeks dominion over his own kind.Place into an Abyssal Socket on an Item or into an allocated Jewel Socket on the Passive Skill Tree. Right click to remove from the Socket.
. Through the flavour text, Tecrod is described as being a slave, presumably to the other Lightless, who seeks "dominion" over them.
His jewel, Tecrod's GazeTecrod's Gaze
Murderous Eye JewelAbyssRequires Level 40+(10-20) to Strength
40% increased Main Hand Critical Strike Chance per
Murderous Eye Jewel affecting you, up to a maximum of 200%
+20% to Off Hand Critical Strike Multiplier per
Murderous Eye Jewel affecting you, up to a maximum of +100%The Hated Slave seeks dominion over his own kind.Place into an Abyssal Socket on an Item or into an allocated Jewel Socket on the Passive Skill Tree. Right click to remove from the Socket. and its basetype 
Murderous Eye JewelMurderous Eye JewelAbyssPlace into an Abyssal Socket on an Item or into an allocated Jewel Socket on the Passive Skill Tree. Right click to remove from the Socket.
, are associated with strength and melee attacks. By proxy, he is associated with those themes as well.
See also: Tecrod, the Hated Slave, Kurgal, the Blackblooded, and Ulaman, Sovereign of the Well, other notable Lightless.