Lernaean

Subtlety may not be their game. But that is still a Cataphractii Terminator you're fucking with.

Lernaeans were elite Terminator infantry of the Alpha Legion during the Great Crusade and Horus Heresy and were essentially the Honour Guards of Alpharius Omegon. Compared to the Effrit Headhunters which are also Honour Guards, the Lernaean were far more conventional and orthodox.

Overview

Given that a Terminator's MO is the direct opposite of Alpha Legion stealth and subterfuge warfare, the Lernaean had limited battlefield potential; being largely regulated as either overglorified bodyguards, ceremonial purposes or as distraction when a Alpha Legion plan did not go as expected and shit hit the fan. At the very least, the Alpha Legion knew how to co-opt the disadvantages of a Terminator into something else. And hid them, the Alpha Legion did very well.

Unknown by the greater Imperium, Lernaean Terminators rarely left behind any evidence or witnesses of their deeds and few knew of their existence. In battle, they slowly advanced relentlessly upon the foe, acting as a bulwark in areas where even subtlety would have been thrown out of the window. Having secured their objective, they stubbornly held against any counterattacks. The Lernaeans were known as the jaws of the Hydra, the bestial symbol of the Alpha Legion itself.

Clad in Cataphractii Pattern Terminator Armour, Lernaeans were armed with Volkite Chargers and Power Axes which made them fierce opponents in close combat. Each squad was led by a Harrower. A squad was usually deployed via a Land Raider (either a Proteus- or Phobos-pattern) but could also be deployed in a Spartan Assault Tank or via a Dreadclaw.

During the Battle of the Alaxxes Nebula, Alpharius disguised himself as one of his own Lernaean bodyguards to confound the Space Wolves.

Crunch

On the Horus Heresy tabletop, they are a Cataphractii Terminator squad for 45 points a pop equipped with Volkite chargers, power axes and a venom sphere on the Harrower. Compared to standard Cataphractii, they upgrade Inexorable to Stubborn (which applies to Fear). They also get It Will Not Die (5+) and Hydran Exemplars, which allows them to claim +1 to hit against one other Legion. They also gain an additional point of Leadership and the squad leader has three wounds. Finally, they are "Line" units so are able to claim objectives, making them one of the only choices in the game for Line outside of Troops and Legion Standards.