Zakum Quests/Bosses

Location: El Nath, Last Mission : Zakum's Altar
Summoning Requirement: Eye of Fire
This quest is not in the European version of MapleStory.

The Altar of ZakumThis quest involves a giant stone boss at the end of The Caves of Trial. In order to face this huge boss, it is required that challengers first do Adobi's Mission (Stage 1), then an extremely hard jump quest, and finally gather 30 Gold Teeth from Minor Zombies in order to forge the Eye of Fire. The boss has eight arms which all need to be eliminated in order to take out the main body, you also have to fight the main body three times. To kill Zakum you need a party of at least level 100 people, with a good mix of classes, especially priests. This boss is considered the toughest boss in all of MapleStory, excluding the Korean, Japanese, Thailand, SEA and Global versions of MapleStory.

Zakum is based on the Muslim belief in Zaqqum, a tree said to grow in hell which provides the only fruit that the damned may eat. This is consistent with the Zakum of MapleStory, as a giant tree can be seen in the background when fighting it, and it must be summoned with a "seed". The boss is supposed to be the physical representation of this tree.
Wikipedia has an article about this subject:

Zaqqum
Tips'

Closing ALL Programs and lowering your resolution is a definite must. Zakum has a tendency to majorly lag/DC people.
Have a decent computer processor, graphic card and RAM. People are known to DC even if they have usually lagless connections, as the image frame loading is extremely high.
You may enter the room with Zakum twice a day (Only once in several versions). The leader of the party has to go in last.
*At least 10 people are required before Zakum's Altar can be entered.

An Eye of Fire is required to summon Zakum, which can be received from the Zakum Dungeon Quest.
The people who go in must have a certain level of accuracy, it is however recommended that you go to Zakum at level 100.
Zakum will be easier to kill if the healing and status arm (third from top, left and right) are destroyed first. Healing arm (third from top at right) heals Zakum 50,000 to 55,000 hp about every 30 seconds.
Meso explosion may cost lots of mesos but can save lots of time if you leave the physical arms and get chief bandits to drop mesos while people kill the remaining arm.
Get at least 8 L135+ Hermits/Night Lords in the Squad.
After all the arms are down, Zakum begins summoning monsters (Puco, Pachu, Punco, Cuzco, Opachu)and drains HP and MP to 1.
Zakum gives 7,000,000 Exp when its final form is killed, split accordingly among all who damaged it, when defeated.
Zakum drops the fabled Zakum Helmet 1 (2 in JMS) when defeated.
In several versions of MapleStory, there are "squad" systems, where a number of parties will assign one overall leader, and registers to wait in line to fight Zakum. Recently implemented MapleGlobal.
A recent update to Zakum made it drop Lv 100 Weapons/Armor instead of lv 90 Equips in certain versions (kMS, jMS, cMS, MSEA). The mastery book drops remain unchanged.
Aside from the Zakum Helmet, it is also hunted very actively in versions with 4th Job due to the drop of two elusive skillbooks.
http://strategywiki.org/wiki/MapleStory/Quests/Party_Quests