Zakum was a spirit sealed in a tree deep in the mines of El Nath. A mining town that once existed nearby eventually discovered this tree. At the time, Zakum was a peaceful monster that had no enemies, but the greed of the miners corrupted it. As the spirit was corrupted, it grew smarter, and finally became capable of controlling the town's populace. It forced them to build an enormous statue in tribute to it. (There is evidence found in the Monster Park that Spiegelmann may have had a hand in building it, which he hotly denies, even to the point of attempting to bribe someone who finds the photo into keeping quiet.) The now evil spirit of Zakum possessed the statue, subjugated all the humans and eventually killed everyone in the town. Zakum now rests deep in the lava caves, waiting for powerful players to challenge his might.
One of the first major bosses in the game, Zakum proves to be quite powerful by inflicting many status ailments and has an array of attacks and summons to keep players off balance. It is advised to have many healing potions as well as All Cures prepared before entering the boss's chamber.
Upon dropping an Eye of Fire (Eye of Fire Chunk for Easy mode) onto the central altar in the room, Zakum spawns and the battle begins. He has eight large arms that need to be taken down in order to fight the main body. Arms 1 (top left) and 2 (top right) will launch an attack that zaps some of a player's HP and MP. Arm 3 (under Arm 1) will launch poison area of effect fields and fire attacks. Arm 4 (under Arm 2) uses lightning elemental attacks. Arm 5 (under Arm 3) does not attack, but severely hampers the party by using seals, blinds, curses, and weaknesses. Arm 6 (under Arm 4) increases all the arm's weapon and magic attack and defense and also heals their HP and MP. Finally, Arms 7 (under Arm 5 and bottom left arm) and 8 (under Arm 6 and bottom right arm) pounds the ground to produce large shockwaves.
Once all eight arms are defeated, the real battle begins. Its body will now do touch damage which is extremely painful. Zakum also attacks with lightning and fire pillars all across the field as well as a wide-ranged area of effect that reduces all HP/MP to 1. It can also put up Weapon and Magic Cancel to render itself immune to respective attacks, and can also heal once in a while. Zakum will also summon Boogies, Pucos, Puncos, and Cuzcos.
After lowering Zakum's HP, its body will crumble; the fight is still not over. In the second phase, Zakum will no longer summon Boogies, but instead summons Opachus. It has even more HP and attack and defense than the previous form, but still retains all its other abilities.
Zakum will once again crumble away, entering the third and final phase of the fight. It will stop summoning Pucos and gains another boost to HP and attack and defense, but none of its abilities change. Once the final body is destroyed, Zakum crumbles entirely, signaling its defeat, and scatters its loot over a wide area.
KMS Battle Overview
Recently, the Zakum boss battle was updated in KMS, using a new 2D skeleton system. Like before, an Eye of Fire is used to summon Zakum (Eye of Fire Chunk for Easy). In this version, there is a 10 second cooldown and an individual death counter of 5 (50 for Easy). Once the player uses up all their lives, they will remain dead until either Zakum is defeated or until all players in the map are out of lives. The arms are still part of the battle, but eliminating them is not mandatory to fight the body; instead, you can fight the body and the arms at the same time for the first 4/5ths of the battle, after which the arms are taken down and you have to finish off the body. However, you can defeat the arms before this, after which Zakum starts using a different attack pattern. However, this will only happen once all the arms are defeated, and the arms will regenerate after a short period of time for Chaos mode.
During the arm phase of the battle, there will be signals on the ground, and the arms will slam onto those spots, instantly killing any players standing on those spots. Occasionally, three platforms will appear on each side of the map, and the ground will be cast on fire, damaging any players that stand on the bottom of the map. During this phase, two arms will clap together and fire a laser that hits the two platforms adjacent to those arms, instantly killing any players standing on those platforms. These two phases will alternate throughout the battle until you reach the last 1/5th of Zakum's HP.
If you defeat all the arms before the last 1/5th of the battle, Zakum will start summoning 2 of each of its minions. Zakum will charge up an attack, remaining stagnant for a few seconds, and then unleash an explosion that does 99% of your health as damage. Zakum will also be able to cast Weapon Cancel during this phase, rendering non-magic attacks ineffective. The arms will randomly regenerate throughout the battle in Chaos mode, but Zakum will continue with this attack pattern until defeated. The arms will also gain a new ability: grabbing the players (only if there are 2 or more people fighting Chaos Zakum at once) and holding the player. If a player does not attack the arm, the player being held will be killed, but will be released if the arm is damaged.
Once you are on the last 1/5th of the battle (if you haven't defeated the arms already), all the arms will disappear and you will be left fighting the remainder of the body. During this phase, rocks will fall from the ceiling, slowing any players and preventing them from using movement skills, such as Flash Jump or Teleport. Zakum will burrow into the ground and reappear in a different spot close to the player. Zakum can cast Magic Cancel, rendering itself immune to magic attacks. Its main attack involves a green cube appearing, and the players must hide under the cube to avoid getting instantly killed by its main attack, where it leaps into the air and slams into the ground.