Difficulty
The difficulty of duties in Final Fantasy XIV can roughly be divided in relatively easy story-mode duties (most content in the game) and difficult but optional high-end duties, aimed at skilled and experienced players.
This distinction is relevant as long as duties are played "synced", that is, without the option "Unrestricted Party" enabled in the Duty Finder. If that option is enabled, duties from past expansions designed for a lower maximal level can become trivially easy to clear or even alone by players with a maximum-level character.
Moreover, lower-level duties are generally easier than duties designed for the current maximum level, because in lower-level duties players' gear will almost always be at the maximum power allowed for by the level sync mechanics.
Story-mode difficulty
Duties required to complete the Main Story Quests and therefore to advance in the game represent the easiest level of difficulty. These include normal Dungeons and Trials (including those misleadingly labeled "Hard"), as well as solo duties required by job or main story quests, and, at level 90, variant dungeons. These duties can be cleared easily "blind", that is, without prior knowledge of the duty.
The first two duties of the level 50 Alliance Raids are also very easy, as they were designed for significantly lower power levels than the ones available to players now.
Higher-level normal Trials, normal Raids and Alliance Raids, most of which are associated with side story quests, are slightly more challenging but can still be completed blind, although there may be a few wipes if most of the party is new. These may include mechanics that have somewhat less obvious AoE telegraphs (for example, players may need to look at the boss's animation or cast bar to find the safe area for an attack, and the AoE indicator will only briefly appear before the attack resolves). Alliance raids may be somewhat easier than normal raids because the large number of players allows to compensate for mistakes more easily.
Higher-level dungeons tend to be easier than dungeons below level 50, because of their streamlined layouts, stricter limits on the number of enemies that can be pulled at once, and the greater availability of healing and mitigation abilities for tanks and healers.
Gear required: Tanks and healers should equip gear close to the character level for which the duty is intended, or there may be the occasional failure. DPS players should do likewise or enemies may take longer than necessary to kill. Generally, all players should equip the highest Item Level gear available to them. For duties at the current level cap, this may include the best craftable high-quality gear purchased from the Market Board, or the gear available from the current weekly limited tomestone currency. More information can be found in the Endgame Gear Guide.
Preparation required: None. (Consulting a guide beforehand may help somewhat, but can spoil the story.)
Consumables required: None.
High-end difficulty
The following duties are considered "endgame" content, representing increasing levels of difficulty, and are aimed at skilled and experienced players. Their difficulty stems not only from the high level of damage incurred by players, and by their increasingly complicated mechanics, but also from the following features:
- Lack of telegraphs. Many damaging effects will no longer be announced in advance by glowing areas on the ground and must be anticipated from visual cues or reading the cast bar to avoid them.
- Party coordination is required. Players must often take specific positions depending on their role. Such coordination can occur through third-party voice chat tools, or by a macro with written instructions for the party to follow.
- Enrage timer. If the boss is not killed in a given time - designed to correspond to the damage output of a very competent party - it will "enrage" and kill the party.
- Low tolerance for error. The mechanics of these duties are often designed such that the entire party, or most of it, will be killed if only one player does not follow the mechanics correctly.
- Mechanical knowledge required. For the above reasons, endgame duties require all players to have a good understanding of the entire fight and its mechanics. This is possible because the fights are "scripted", in that the mechanics always follow the same order, even though they will often contain a degree of random variation.
- Mitigation required. While party mitigation is essentially optional for bosses in story-mode content, raidwide damage in high-end duties, especially later-floor savage raids and ultimate raids, will often kill DPS and healers in one hit unless if there is sufficient mitigation. "Tank buster" abilities will also kill tanks if they do not use mitigation.
Extreme and unreal trials
Extreme Trials are the endgame content most accessible to newer players. They are much more difficult versions of the corresponding regular trial. The most current extreme trial will drop weapons that are more powerful than the ones otherwise accessible outside of savage raids. Unreal Trials are older extreme trials that have been scaled up to the current level cap and have a strict item level sync, preventing players from out-gearing them. Criterion dungeons are extreme-difficulty versions of variant dungeons.
Extreme and unreal trials are usually 10-12 minutes long. The damage output requirements are relatively lenient: a typical party should not fail because of the enrage timer unless there are many deaths.
Gear required: All players should equip the highest item level gear available to them, enhanced with the best materia available. Gearing is less important for unreal trials due to the low item level sync.
Preparation required: While it is possible to beat an extreme or unreal trial "blind" with some trial and error, most players will prepare for the trial with a video guide.
Consumables required: Players should consume the highest-level food that boosts the attributes required by their job.
Savage raids
Savage Raids represent a medium difficulty within the scope of endgame content. They are much more difficult versions of the corresponding regular raid. The most current savage raids will drop weapons and gear that are the most powerful available in the game, which are also often required to progress from one savage raid to the next. The level 50 Coils of Bahamut raid series is of savage rather than story-mode difficulty, even though not labeled as such. There are also savage-difficulty versions of criterion dungeons.
Savage raids are similar in length to extreme trials but have higher DPS requirements, although these become more lenient with time due to better gear. The fourth floor of a savage encounter with week 1 gear usually contains the tightest DPS checks in the game.
Gear required: All players should equip the highest item level gear available to them, enhanced with the best Materia available, and aiming for a "best in slot" setup consisting of a mix of tomestone and raid-dropped gear.
Preparation required: Most players will prepare for the trial with a video guide in order to clear in a timely manner. However, some groups of players choose to "blind prog", i.e., figure out the mechanics on their own without any outside assistance, although these groups are rarer than those that expect preparation through guides.
Consumables required: Players should consume the highest-level Food that boosts the attributes required by their job. They should also consume Medicines, commonly called "potions" or "pots" by players, (ex Grade 7 Tincture of Strength) as often as possible during the fight.
Ultimate raids
Ultimate Raids are exceptionally challenging duties, harder than savage raids. Their rewards are only cosmetic in nature.
Ultimate raids are very long (14-20 minute) encounters against a gauntlet of bosses. DPS requirements for older ultimate raids are relatively lenient (comparable or even less than that of a current extreme trial). Ultimate raids in the current expansion have more notable DPS requirements, but these are more lenient compared to fourth-floor savage raids in low item level gear. However, individual mistakes are much more punishing.
Gear required: For the newest ultimate raid in the current expansion, all players must equip "best in slot" gear at the highest level available in the game, obtained from savage raids. For ultimate raids that were released earlier in the expansion, players should use "best in slot" gear that matches the item level sync, so materia melds will be applicable. Specific gear sets are less important for ultimate raids released in previous expansions, and players can simply equip current item level gear which will sync down.
Preparation and consumables required: As per savage raids, above. Mechanics in ultimate raids can be exceptionally cryptic to solve, so the vast majority of groups will use guides, and "blind prog" groups are very rare, especially for older ultimate raids.