Last updated: 7/3/23
Deep dungeon is basically FFXIV's roguelike side content. A deep dungeon consists of 200 (Palace of the Dead) or 100 (Heaven-on-High and Eureka Orthos) floors with randomly generated layouts. To proceed from one floor to the next, parties must explore to find the exit and kill a random number of enemies to open it.
Floors come in sets of ten, with a boss at the end, and you have one hour to clear a set. The floors get harder the deeper you go, to the point that regular enemies can and have wiped entire parties in the blink of an eye. To complicate things, there is a form of permadeath past a certain point (floor 100 in Palace of the Dead, floor 30 in Heaven-on-High and Eureka Orthos). While individual party members can still raise each other, if the entire party dies, they will be forced to start over from the beginning of the deep dungeon. That means that if your party dies on floor 199 in PotD, you are locked out of that run and must start over from floor 1 (or the sole checkpoint on floor 51, though this renders you ineligible for some achievements).
In addition to random layouts, floors have:
Randomly placed invisible traps which inflict detrimental effects when stepped on, like turning you into a helpless critter or spawning three enemies on top of you.
Occasional "enchantments," status effects that are active for as long as you're on that floor. Enchantments can be positive or (more often) negative - for example, they can increase your HP/MP, make enemies stronger, increase your speed, or take away your abilities.
Randomly generated chests which contain a variety of things. The most notable are gold chests, which contain pomanders, an item unique to deep dungeon. Pomanders bestow powerful boons when used, such as massively increasing your defense, removing all traps from the current floor, or even automatically raising someone if they die, basically serving as an extra life if used in a pinch. Pomanders must be gathered within a specific run (no carrying over pomanders from one run to another) and there is a limit to how many you can carry.
(But also, sometimes the chests are mimics!)
The current deep dungeons are:
It's exactly what it sounds like. You go into a deep dungeon alone, and try to make it all the way to the top on your lonesome. Enemies, floor layouts, etc are exactly the same as they would be for a four-player party, and the permadeath rule is still in full effect - which means that you have to start all over if you die, and there are many, many opportunities to die!
Successfully soloing deep dungeon, all the way from floor 1, rewards you with a neat title: "The Necromancer" for Palace of the Dead, "Lone Hero" for Heaven-on-High, and "Once and Future [King or Queen, depending on character gender]" for Eureka Orthos. There aren't any material rewards beyond that. Some people do it for the bragging rights, but most of the people in the deep dungeon scene also genuinely enjoy the challenge.
The idea that you need super good RNG to clear is a huge misconception, actually! Deep dungeon solo is much more complex than barging through and hoping for the best - it involves knowing how to avoid traps, how to avoid being seen, how to use pomanders effectively, which enemies are safe to fight and which to avoid at any cost, strats for managing tricky enemy and boss mechanics...
If you look at individual soloists' progress, you'll see that the highest floor they reach trends upwards the more runs that they do. The most experienced runners can consistently clear on their job of choice, with some even clearing challenge runs such as not using potions or not opening chests past a certain point. Knowledge and experience matter far, far more than luck.
As one deep dungeon runner put it: "You don't need good RNG to clear. You just need to know how to manage bad RNG." And as my partners put it, the main appeal of deep dungeon solo is the thrill of using everything you have at your disposal to overcome the most overwhelming of odds.
As of 6.4, 1% of players have soloed Palace of the Dead, 1.1% have soloed Heaven-on-High, and 1% have soloed Eureka Orthos. (This is going by how many characters have the achievements - the actual number might be slightly lower when you factor in alts.) For comparison, 2.5% of players have cleared The Omega Protocol ultimate.
Every job has soloed every deep dungeon!
The jobs generally considered the "easiest" for solo, as of 6.4, are:
Palace of the Dead: machinist (you can kite enemies to avoid damage and kill them before they kill you) and warrior (you have tank privilege and ridiculous self-healing)
Heaven-on-High: summoner (like machinist but burstier at 70) and warrior (same reasons as before)
Eureka Orthos: (I actually do not know for this one, but word on the street is that it's the easiest and least RNG-dependent deep dungeon, and that you'll be fine with almost any job as long as you know what to do.)
Meanwhile, astrologian is universally considered the hardest solo job due to being scaled around party buffs - clearing on AST requires very clever resource usage, multipulling dangerous enemies, and tight optimization of your buffs/damage rotations. If you clear on AST, you are basically a deep dungeon god.
That being said, that doesn't mean that the other jobs are bad, per se. Every job has strengths, weaknesses, and its own playstyle that gels differently with everyone. It's very possible that you might find the "easy" picks tricky or frustrating but do well with a more niche job - don't let ideas of what you should play hold you back!
This depends on who you ask! Many people prefer Heaven-on-High because there are fewer floors to reclimb than Palace of the Dead, and the pomanders are easier to use. Palace of the Dead also has an infamous boss on floor 180 that requires an extensive setup for anyone who isn't a healer or red mage. However, the enemies in Heaven-on-High also hit harder and are more dangerous to fight without good resources, leading some to find Palace of the Dead more consistent.
As of its release, Eureka Orthos is considered far and away the easiest - although enemies are tanky af, they are very predictable and don't pose as much a danger to you if you stay on top of their mechanics, and there's significantly less pomander management needed in order to stay ahead of time, especially as a DPS.
I sure do!
There are a number of streamers on Twitch who stream deep dungeon solo content. I'm personally fond of AngelusDemonus and AuroraMoon - both are highly experienced runners who've cleared both deep dungeons on all jobs, and both are always delighted to meet new soloists and answer their questions. (Angelus also showcased deep dungeon solo at AGDQ 2023!)
For guides, Maygii's Palace of the Dead guide and Heaven-on-High guide are a good general resource for parties and soloists alike - that being said, keep in mind that the solo bits are written from the perspective of a red mage, and that specific enemies might be harder or safer to fight depending on your job. There's also DDCompendium. (Eureka Orthos guide TBA)
There are a number of other guides floating around, including some job-specific ones, and people have also uploaded their runs (some with commentary) to Youtube. Angelus's Discord has links to a bunch of them. (I might also make my own compilation post for those who don't want to join a Discord.)