So you poked around a couple of forums and looked up a few things on wiki, just to find yourself on information overload. Don't worry, it's understandable; even hardcore players were a bit overwhelmed as we were thrown into these crazy new add-ons. It took months of testing and observation to figure out the mechanics we now know.
Most of this information is available on Wiki, but it's strewn about in various articles and not geared toward someone who's fresh and new to Abyssea.
In this post I'll attempt to sum up most of the mechanics of Abyssea in an easy-to-understand format. At the end I will answer a few of the most common questions that we've been seeing from returning players like yourself.
The BasicsStoryline: Unlike previous expansions and add-ons, there is no story-rich, involving mission line in the Abyssea expansions. There is a main series of quests that progresses as you kill the boss of each Abyssea zone (and these yield very powerful rewards) but don't expect climatic twists, tear-jerking moments, or new, loveable NPCs. Each zone also holds a plethora of fetch quests and goal quests which yield rewards, and each zone has its own unique fame/reputation levels required to progress in these small quests.
Key Items: Nearly everything about Abyssea involves obtaining and using Key Items. There are many types of Key Items, and very, very many of each type. Key items dictate your time allowed inside of Abyssea, the buffs you obtain upon entering, how many of those buffs you can receive, the exp and loot you can obtain, and even what Notorious Monsters you can pop.
Entering Abyssea: The initial time you are allotted to stay inside of Abyssea revolves around the usage of another Key Item called Traverser Stones. Each Traverser Stone allows you 30 minutes inside (Visitant Status), and they regenerate at a rate of 1 every 20 hours. They are distributed to you by speaking to the NPC Joachim in Port Jeuno.
Your time in Abyssea can be expanded by obtaining Key Items that make Traverser Stones regenerate at a faster rate, Key Items that make your Stones reward you with more time each, and by obtaining time extensions while inside of Abyssea.
You start building up Traverser Stones the very first time you talk to Joachim after purchasing an Abyssea add-on. For this reason, it's suggested that you do so as soon as possible, even if you don't plan on participating in Abyssea right away.
Currency: The monetary unit for Abyssea is Cruor. You obtain Cruor by defeating monsters, Notorious Monsters, and completing quests. Cruor is used for travel and the purchase of certain Key Items, gear, and temporary items.
Travel: Each zone has a series of 8 or 9 conflux used for quick navigation around the zone. It is suggested that you obtain all conflux in each zone as soon as possible for easy travel. You may also warp directly to any Abyssea zone you have previously visited by speaking to the NPC Horst in Port Jeuno.
Monsters: Mobs inside of Abyssea are not strewn about like in other FFXI zones. They are in large clusters of a single type and restricted to a single large area. These mobs can increase in level as they are defeated, making them more difficult as you continue to kill them. They can also despawn and reset their level if left alone long enough.
Lights: A mechanic exclusive to Abyssea, and a very important one. Whenever you kill a monster inside of Abyssea, you gain a certain 'light'. The color of light is determined by what method was used to kill the monster; killing with magic will grant you Azure light, physical weaponskills give Ruby light, elemental weaponskills give Amber, and physical melee kills grant you Pearlescent light. These lights stack upon each other, and are not overwritten by other lights.
Lights determine the frequency and color of pyxide (see next paragraph) that drops from a monster you kill. There are also other colors of lights which can only be obtained from opening red pyxides.
Treasure Chests: Called 'pyxides' in Abyssea, these can be opened by guessing a combination or using a Forbidden Key (purchased with Cruor). There is a chance of these pyxides dropping whenever a mob is killed. Pyxides yield different rewards dependent on what color they are. The rewards include experience points, cruor, more lights, gear, items, key items, and time extensions.
Abyssite: Key Items obtainable from Notorious Monsters and completing quests. These have a wide variety of effects from increasing your time inside Abyssea to boosting your base statistics. These are only active while inside of Abyssea with Visitant Status.
Atma: This is where the true power of Abyssea comes from, empowering adventurers to levels you've never seen. Atmas are Key Items which can be equipped while inside of Abyssea, obtained by defeating specific Notorious Monsters. Many Atmas are incredibly powered buffs, stronger than any equipment available in FFXI.
To equip an Atma, one must have a certain Key Item called Lunar Abyssite. There is one Lunar Abyssite available in each Abyssea add-on, resulting in a maximum of 3 Atmas equipped at a time. Lunar Abyssites are obtained in different ways for each add-on.
Experience PointsAh, now we're getting to what you're really interested in. The EXP mechanic in Abyssea is drastically different than the rest of the game.
Alliances: The ever-coveted EXP chain is gone, being replaced by an entirely new type of chain. Each mob killed of the same type increases the experience reward by a small amount each kill, and isn't determined by how fast you kill x amount of mobs in y amount of time. It's possible to reach 620 exp per mob, which makes it possible to obtain upwards of 150,000 exp/hour or even more in a good alliance. Killing a mob of a different type will reset this chain for the entire alliance.
Dominion Ops: The same as above, but these alliances also involve the completion of Dominion Ops to supplement your EXP gain. Dominion Ops are a sort of side quest available in Heroes of Abyssea, and it involves killing a certain type of monster so many times. Upon completion you are rewarded with EXP, Dominion Notes (which can be used to purchase augmented weapons) and upgrade items for AF3+1 (see Empyrean Armor below).
Leeching: The goal of an EXP alliance is to build certain types of lights to increase pyxide drops, thus increasing the rate of exp gained and awarding time extensions. Opening these pyxides can be a full-time job, since the alliance will be killing monsters as fast as they can. This is where a leech comes in: nobody cares about the job level or abilities of the leecher since they aren't directly involved in the killing.
A leecher is often a person on a low-level job (level 30 is required to enter Abyssea) who purchases a ton of Forbidden Keys and opens the pyxides for the alliance. EXP will climb slower for a low-level job, but can still ultimately hit 600-620 EXP per kill, making it possible to level up at an incredible rate. Leeching can often times be profitable as well, since there is potential for items and augmented weapons to be obtained from boxes.
GearWith the level cap increase, some fresh new gear was needed to reflect our new levels. There is a plethora of armor and weapons to be obtained in Abyssea. There are many pieces of gear which drop from Notorious Monsters using weakness targeting (see 'weakness targeting' below), and some are specific sets obtainable only with persistence, skill and patience.
Cruor Equipment: Easily obtained gear which is purchasable with Cruor or from Auction House. Great entry-level gear to fill the gap until you can obtain Empyrean Armor (AF3).
Empyrean Armor (AF3): Incredibly powerful, job-specific gear obtainable in Abyssea.. There are 3 stages to each piece of AF3: base gear, +1, and +2. Base gear is usually easily obtained and has very underwhelming stats. +1 gear is a tremendous upgrade and +2 expands it even further. Upgrades are completed by undertaking Trials which involve collecting drops from Notorious Monsters or completing quests.
Empyrean Weapons: Drastically powerful weapons obtained by killing specific Notorious Monsters and collecting their drops. Empyrean Weapons are based on Trial of the Magians and require many requirements to obtain. These are upgradeable every 5 levels and are comparable to Relic and Mythic weapons, but much easier to obtain by comparison.
Notorious Monsters:Abyssea is virtually bursting with new Notorious Monsters for you to destroy! Some of them are on short respawn timers, some are popped by using items, and some are popped by using Key Items you obtained by fighting other NMs.
Weakness Targeting: Another new mechanic exclusive to Abyssea, specifically for manipulating Notorious Monsters and what they drop. To trigger a weakness, one must use a specific spell or weaponskill on a NM, and must complete this action while the NM is neither using a special move nor casting magic themselves. When a weakness is triggered, a colored '!!' will appear above their head and the monster becomes 'staggered'. This will have a specific effect on the NM:
Yellow !! is triggered by casting a specific spell, the element of which corresponds to the Vana'diel calendar of the previous, current, and next elemental day of the week. This causes the NM to be unable to cast magic while staggered and will increase the drop rate of Empyrean +1 and +2 armor upgrade items.
Red !! is triggered by using a specific elemental weaponskill. This causes the NM to be terrored and unable to perform any action while staggered. Triggering this nearly guarantees that the NM will grant it's Key Item (Abyssite, Atma, or another NM pop).
Blue !! is triggered by performing a specific physical weaponskill. The weaponskill's damage type will vary depending on the Vana'diel time in which the NM was claimed or popped. Triggering this blocks the NM from using a special move and greatly increases the chance that it will drop a rare piece of equipment.
Common Questions:"Are my jobs still desirable?"
While every job still has some use in Abyssea, the usage of Atmas has had an effect on which jobs are most desired. A few examples: White Mage is now the king of healers and requires little to no support thanks to a nearly infinite MP pool. Bards and Black Mages are rarely needed for support and damage, but they are in high demand for yellow weakness targeting. Red Mages, arguably the most desired job in the game outside of Abyssea, have extremely little use inside of Abyssea since their cures are lacking and enfeebles are unnecessary. Dual Wield jobs such as Ninja, Thief and Dancer are seeing success thanks to boosts to Double/Triple Attack and critical hits. Monk is now the tank of choice with their damage abilities, large HP pool and Counter.
"I'm so behind! Is it possible to get caught up?"
Yep, and probably quicker than you think. Currently the only way to teleport to Abyssea zones is from Port Jeuno, which means a large chunk of the playerbase keeps their Home Point there. There are constant shouts of people seeking help with NMs and building EXP alliances. Use this to your advantage and join them for Abyssites, Atmas, or even gear! Make a few friends, have fun, maybe even find a Linkshell or small group of players who regularly spend time in Abyssea.
"My Linkshell mates are all gone. ;; Can I get anywhere without a Linkshell?"
While it's obvious that there are many benefits to having an endgame LS, it's far from necessary for Abyssea. In fact, most players would agree that it's far more efficient to lowman Abyssea NMs for their drops. Virtually everything can be duo'ed or trio'ed by skilled players, avoiding unnecessary TP feed to the NM and resulting in a cleaner fight. This leaves room for another player or 2 to come on jobs specifically aimed towards getting !! procs for better drops.
"Do I need to purchase all 3 Abyssea add-ons?"
Edit: SE has now released 'Final Fantasy Online - Ultimate Collection - Abyssea Edition', making this question a bit redundant, since you can now purchase the entire game, every expansion pack, and all add-ons for less than the original price of 2 Abyssea add-ons.
While you don't need to own all 3 add-ons, you'll be hindered without them all. Each set of zones has unique rewards, and each add-on gives the potential of equipping another Atma. I understand that purchasing all 3 is quite an investment: it's significantly more expensive than purchasing the entire rest of the game and expansions. If you're strapped for cash or leery that you might not like the game, my suggestion would be to purchase one of them for now so you can start acquiring Traverser Stones.
Is it worth coming back?
The majority of posters here are still playing, so there's your answer! It's common consensus that all the changes made thus far are for the better, and many of us are enjoying the game more now than we have in years.
Welcome back to Vana'diel!
Edit: Since making this guide, the Abyssea section of FFXIClopedia has been updated and now provides a good overall summary of Abyssea.
Edited, Feb 23rd 2012 8:45am by Chewzer