Dominus Hilarus was migrated from the great underground earth colony, Onu-Koro during the early Rahi invasions. At the time he was very young for a miner, and had no knowledge in combat whatsoever. He could not help his friends and family as they were destroyed by cave-ins, and the massive attack of the rebellious creatures. He fled south (above ground) by foot with other survivors, not trusting any animal to assist him, now that Makuta's reign over the Rahi was strongest. The others did not last long but Hilarus strode on. It was getting increasingly cold as he walked, until he collapsed into the deep snow of Ko-Kini, losing his mask and going into a state of unconsciousness. He woke up later in a house warm, and pleasingly comfortable. He looked around and realized that despite the warm temperature, he was in the land of cold; Ko-Koro-City of Ice. He sat up, on the cushioned bed, but collapsed once more. Not from the cold this time, but a custom set of armor that was placed on him. He would later find out that the great Ice Toa, Kopaka, designed it to be like his new armor. It regulates the users' body temperature to be fitting enough for the weather conditions. The people of Ko-Koro hadn't had a good chance to test the suit, but now they knew it worked. After familiarizing himself to the snow, ice and people of this new and interesting land, he learned their way and passed their initiation test, becoming one of them. With that, they replaced his lost Kanohi Kakama with that of a deceased warrior. It was Kanohi Akaku and it's specific power was insight, and quite literally too. He not only could predict the enemy attack, but see their weak points and through their lines with x-ray. He trained as a warrior, as Jala (renamed Jaller later) and the great chronicler moved towards finding the Toa of light. He works for the ice matoran now as a protector. All he asks in return is when he is no longer able to help them, they escort him back to his homeland, but for now, he reigns the south.
Hilarus carries a leaf blade and laser rifle. On his boots are attached two titanium "toe protectors."
Ego Diligo Vir does not yet know that Hilarus is his father.
As we speak, Dominus Hilarus is striding towards Le-Koro to make a diplomatic agreement with a major tribesman. His status has not been reported, but is expected by tomorrow morning, if not earlier.
He has reported his mission in Le-Koro a success. He obtained a hefty ration of firewood and is going to have it mailed by air-born rahi. Hilarus is spending time in the forest before his return and should be back in Ko-Koro tomorrow.
Hilarus is back in Ko-Koro, unemployed. No new threats.
Dominus Hilarus was seen slain in battle against Rakshi. A disk thrower saw that as he shot a poison rakshi, another impaled him through the thigh. He turned around and was slashed by a bohrok; this time a mortal wound to the chest. Another poison rakshi pierced Hilarus through the mask, killing him. His body, along with all others involved in the battle who had fallen, had never been recovered.