From FFXIclopedia:
Limbus is a mysterious dimension that lies between Vana'diel, Promyvion, and Lumoria. It is accessible from the celestial realm of Al'Taieu [(Sea)]. Similar to Dynamis, these areas are intended as a challenge for advanced players at the highest levels. Items can be obtained here that can be redeemed for upgraded Artifact Armor and Rare/Ex equipment.
Limbus is comprised of two [regions]: Temenos and Apollyon. Each [region] has separate areas leading to a "central" area, eventually leading to a boss fight with a prototype biotechnological weapon. Items obtained from these bosses can be redeemed for pieces of two high-level sets of armor from the Near East.
As a clan, we are primarily interested in Limbus for specific items:
Limbus is a Dynamis-like area. It is only accessible to those with special key-items who already have Al'Taieu (Sea) access. Once a group has entered a Limbus area and engages their first mob, that Limbus area is closed off and no others can enter that area until the first group has exited (by completing the Limbus area, running out of time, or wiping).
Once inside Limbus, you have a time-limit (30-60 minutes, depending on the area) to complete some specific tasks. These tasks often include ascending levels and defeating bosses. Enemies defeated will drop beastcoins (which can be sold, or used to obtain AF+1 armor) and occasionally special armor items.
Because Limbus is timed, it is absolutely vital that no one goes AFK after the event is scheduled to start. Persons who go AFK inside of Limbus will be dropped from their party, no questions asked. We will have zero-tolerance for people who go AFK (announced or unannounced) during Limbus. If you go AFK, you will forfeit your claim to any drops obtained that night.
After Limbus starts, no one else can join in (the Limbus area locks down). This means that you cannot show up late and expect to be able to participate. You can show up late and cheer us on from the LS, but don't expect any of the drops or to be able to participate in the event unless you show up on time.
In order to enter Limbus, you need two key-items:
For ClanAM Limbus events, we will meet at Sagheera in Port Jeuno. After everyone has purchased the Cosmo-Cleanse, we will then teleport as a group to the Dimensional Portal we wish to visit. Once inside Al'Taieu (Sea), we will farm and kill Aw'euvhi as a group to ensure everyone has the key card. Even if you farm this key card outside our group, you will still be required to come with us to kill this NM! Because there are multiple key cards, we have to ensure everyone has the same one, and farming for them as a group is the best way to ensure that.
After everyone has the two key-items, we will meet at the entrance to the Limbus zone we wish to enter.
Do not enter the Limbus zone until the group leader says so! If you enter too soon, you may close the area and lock your fellow clan members out of the zone!
As we kill enemies, two different types of items will drop: Ancient beastcoins, and AF+1 Rare/EX items. The policies for distributing these items are as follows:
There will be one pool-holder for the event. This pool holder will lot on all Ancient Beastcoins and hold them for the group. Everyone else must pass on the Ancient Beastcoins! At the end of the night, the Ancient Beastcoins dropped will be divided up equally among those who participated. Any extra beastcoins will be added to the group pool for the next event.
AF+1 is hard to obtain. You have to collect a lot of Ancient Beastcoins, some high level crafted items, as well as the Rare/EX drops from Limbus. Because AF+1 is hard to get, and because the AF+1 Rare/EX items cannot be traded, it is important that only those people serious about the AF+1 items for their job(s) lot for them.
We will rely on the honor system for AF+1 lotting, however, we must stress the importance of not lotting on these items unless you a) are serious about the item, b) can actually use the item, and c) no one else needs it more than you. For example, if we have 2 WHMs trying for their AF+1 items, and one WHM has all but one AF+1 item, then that WHM should get lotting priorities.
Because Limbus is timed, we wont have time to squabble over who gets what.... so please please please discuss with your fellow clan-mates before hand what items you are going for and be fair. Any conflict resolution for specific AF+1 items should be dealt with before we enter Limbus.
There are 3 different types of chests that can drop from mobs in Limbus:
Each event there will be one or two dedicated "chest spotters". They will be the only people who can authorize opening a chest.
Basic rule of thumb is, if it's a chest, don't open it unless one of the "chest spotters" or group leader tells you to.
Limbus is very complicated, and we wont cover any further details on it here. What we've talked about thus far will be enough for you to join us in ClanAM Limbus events.
However, if you want more information, I suggest reading the following links: