[FAQ] • [doc]

The Penance King, true name Cacus, is the boss of hard mode Barbarian Assault. He cannot be defeated by normal methods and can only be damaged by flamethrowers created during the fight. Upon killing the king, players are awarded 210 points in their role and 15 points in the other roles.


Cacus was once one of Hostilius's dukes. After Zaros was banished and Zamorak led a rebellion against the Chthonian demons, Cacus and the rest of his kind were either slaughtered or banished to the Abyss. Here he brooded and survived on detritus brought to him on abyssal currents, and said currents slowly moved him closer to the world of Gielinor. He sensed a Fremennik named Aesa Fellsdottir in her dreams and devoured her soul. Aesa isolated herself in an underground cave and awaited her death, after which he created a portal from her body and entered Gielinor. Now calling himself a king, he spawned Penance Queens from his own essence, which in turn spawned the Penance race ubiquitous to Barbarian Assault.

Players will learn this information by purchasing and reading the barbarian assault lore book #1 and #2.



The Penance King does not attack with a specific combat style, although he is only able to attack players in melee range. Each of his attacks deals typeless damage equal to 25% of his target's maximum life points, increasing to 33% and 50% every time an incantation is completed.

He also summons King spawns with 250 lifepoints that follow players and explode upon touching them, dealing typeless damage to all players in a 5x5 area of effect equal to 25% of their maximum life points. If a king spawn is killed, they immediately explode, dealing the same damage, and if they are left alive, they eventually explode on their own.

Resonance can block all damage but not heal from the Penance King's attacks and the spawns' explosions, and other Defence abilities are able to reduce the damage as well.

Gathering for flamethrowers

The flamethrowers are created by gathering various items which the king vomits when he eats a poisoned meat when he says he's hungry (e.g. hides, metal scraps, rusty buckets). Poisonous food is found on the west. An anvil (for collector/attackers) for metal scraps and vents (for defender) to dry hides are located to the east while the buckets (for healers) need to be used on pools of acid (king's vomit). When 5 of each item per role are collected they can be deposited in the west. The flamethrowers will then be available for the team.

A Healer is generally the one who feeds the king. A commonly used tactic has a Healer at the healing spring clicking on it rapidly to replenish their life points, all the while feeding the king when he indicates his hunger. The other four teammates stay at the east side of the arena and move west when the Healer tells them that the king has been fed enough. The teammates must then pick up their appropriate item, then refine the items, and finally deposit the refined items at the chute. When a message says that the flamethrowers are available, go to the chute and take the flamethrower.

The incantation

Fighting Penance King

A team of players use their flamethrowers to damage the king.

Scrolls are dropped by the Penance King when a player attacks the him with any normal weapon. Note that the a dropped scroll is only visible to the player who attacked him and caused it to drop. It is advised to use magic or ranged to attack him as melee is extremely dangerous. It may take several attempts to receive the scroll, as one may miss. A scroll is dropped when the player sees a message saying that the King is resistant to their attack.

When a scroll is picked up (1 per player) 5 words; Labefacto, Flamma, Ignis, Debilito, and Exuro; in a certain order appear on the screen. Inspecting your scroll tells you what word is on your scroll. When all items are gathered every player should say their word when the previous has been said. The order in which they have to be read is from left to right. Reading the word is done by clicking on the word you have in the on-screen interface. Once the incantation is complete, everyone must attack the king while wielding their flamethrowers. Ignore the message that says you are prohibited from attacking due to an item equipped.

This brings the King down to two-thirds of his life points after which he will once again become immune to damage, which is indicated by cracks appearing on the ground beneath him, which deal damage for 33% of maximum life points. To avoid this, the players must use the Escape ability after attacking him with the flamethrowers. He will once again summon King spawns (hitting only 25%) to his aid, and the king will hit harder. The scrolls must be re-obtained and the incantation must be done again, although the flamethrowers are kept. Getting the scrolls and using the flamethrower will need to be repeated at least 3 times (or 4 times, if some players did not attack to the fullest) in order to kill the Penance King.


Barbarian Assault News (3) update image

Concept art for Cacus

  • The Penance King's life points are the first seven digits of pi.
  • Cacus is a fire-breathing giant in Roman mythology.
  • The concept for the Penance King and Barbarian Assault Hard Mode was pitched by PrimalMoose at RuneFest 2013. A poll was later released to all players to decide by which method the King would be defeated, with "weapon of power" winning the poll.
  • The words on the scrolls are all in Latin/Infernal, seeing as Cacus originates from Infernus.
    • Labefacto translates to "I destroy", "I ruin", or "I overthrow".
    • Flamma translates to "fire" or "flame".
    • Ignis also translates to "fire".
    • Debilito translates to "I cripple", "I debilitate", or "I disable".
    • Exuro translates to "I burn".
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