Read the original topic here.
README: This guide is a revamp of my older spiral guide (which I changed to pm-only) so I'm not too certain all the links work. All the info should be accurate as of today 03/02/16.
The layout of this guide is a bit different than others in that it is not linear or chronological. This is because the labyrinth has no set path, so I have found it easier to simply explain all types of non-boss rooms and then explain all bosses. If you need a guide that does it in order, freedomplays has one. Also, apologies beforehand for paragraphs of text. It's all important. I swear.
Images are now uploaded! Get the full album (chronological order for one run) here. I'll also include them in a post below.
Brief Overview of Dungeon Layout
Spiral Labyrinth is not so much a labyrinth as a "you are forced into the next room/a certain path." The way progressing through this dungeon works is that you <clear> a room somehow, which then allows one of the 3 remaining sealed entrances to open and lead to your next destination. You don't choose which path to take, and it’s mostly random. I will now describe the 4 main types of non-floor-boss rooms you will encounter, no matter what floor of the labyrinth you are on.
The <Boss>-type room:
This room is arguably the most familiar and easiest to figure out what to do. You simply need to kill the boss placed in the room in order to progress. The bosses will be either resembling the one from Mushin Floor 5, any Big 4 dungeon, the shelled bosses from the Desert-area purple dungeon, or other familiar bosses. You should probably know how to kill these already.
In these types of rooms, light-blue-lightning-type lasers will occasionally sweep if you take too long. Just jump over them (do a running or strafing jump rather than straight up and down) to avoid. Otherwise, they will shock you and daze.
The <Captain> and <mobs> type room:
This room type is sometimes easy, sometimes hard. Don't rush ahead. While the only requirement for opening the door is killing the captain, some captains may call the entire room to them which results in wipe. Try to just follow your party's lead here, and damage the captain more than the other mobs.
The <Chance> room:
This room will either have a bunch of [f]-key-able pillars, or destroyable stones, or one switch and wheel. Each of these is different.
The pillars should only be opened one-by-one as they either release difficult mobs or a blast of air that instantly one-shots (or 30k hits) everyone. If you have dandelion or ice flower, the moment a pillar is opened cast it. Other tactics include waiting in the previous hallway, or waiting one second and using SS or some other i-frame.
The destroyable stones will simply be kill a stone -> spawn some mobs -> kill those mobs, until room is clear. Just don't be overwhelmed.
The single switch and wheel is a chance to see what mob is spawned in that room. Just kill whatever spawns and move on.
The <Floating Rocks> room:
The fastest room to pass through. You will use various qinggong skills to float to rocks and kill all the mobs that are on the floating rocks in the room, whilst ignoring the mobs on the floor. When you reach the other door, there will be a switch to open that door. This switch also sweeps the room of mobs using a laser.
If you have fallen down, simply wait for your party to clear the room (Caveat: if you have a dash skill, dash to the nearest mob on a floating rock to cheat). If you see a laser coming because your party has moved on, jump over it. If you end up dead, wait and see if anyone is going to revive you and if not, just run back.
Now we've covered pretty much the entire dungeon except the bosses! That will be done here. I'm not cool enough like some guides that explain boss patterns and timings in hard numbers, but rather through graphics and observation.
First Floor: Minotaur:
The only limit here is how fast you can put him down. There are a couple attack patterns here that I will list below. Bold is important. Observable graphics are colored orange for easy reference)
- Melee attacks: just avoid the guy, he's really huge and pretty much a giant HP bag.
- Jump (rears back and jumps onto where the tank was standing): avoid really easily. This only occurs if tank is too far.
- Pre-charge (3 ghostly small minotaurs appear in the tank's direction and run him over): just avoid or dandelion as necessary. If you are tankier than a glass-cannon build forcemaster with only 11k hp, you won't die. I swear.
- Charge (the 4 doors in the wall glow red, he starts steaming and has a blue shield, turns in a random player's direction and charges in that direction until he hits a wall or door): The wall does nothing to him and he will charge again at a different player. The glowing red doors in N/S/E/W directions, however, make him "dazed" and get him “stuck" in the door, meaning higher damage for all of us and without attacks to worry about! Don't flip him into the air or get him out of the door earlier than necessary. For the grabs or aerials, wait 7 seconds first. In order to make sure you have the minotaur crash into a door, you must stand in a linear path between him and the door once this phase starts. Typically failure at making the minotaur crash into a door is what causes parties to fail the boss timer.
- Red circle appears on ground near minotaur, he starts emitting steam again: This is pretty much the giant knockback all melee bosses have. Stay out of the circle range or use i-frame. If its a smaller circle, he'll be doing the spinny thing all melee bosses have.
- A bunch of ghostly minotaurs appear near the wall: Position yourself between their gaps (it's pretty much every other space is a minotaur) and no harm done. Dandelion or ice as appropriate if necessary.
- Red lasers (the electric lasers being sweeping in from all directions)：if you value the boss timer, jump over these! Each laser, last I recall, adds HP back to the boss. That's terrible and the number 2 reason why people fail first floor due to timer.
Second Floor: Clown
This boss is arguably the most difficult due to his OP attacks, insta-kill attacks, 3 elite force master adds, and HP regen. I will first write guides for blade master, summoner, or force master behavior before writing overall guide to this boss. The blade master part only applies if the summoner is not present or their cat dies. Bombing (see below) is only left to force master and summoner because those are the classes with the fastest in-battle health regeneration that simultaneously do not lose DPS from standing at range (warlock as well I suppose), and each bomb will take out like 7k hp of the player.
[Adds] Summoner has priority over blademaster in this job, so observe your summoner if you have one to figure out what is going on. If you are on the final evolve and can regularly finish 4-man instances as well as know how to block like a boss, then this job is for you. Grab the aggro of all three of the elite force master adds. They will fireball you and force-choke you if you do not block correctly. The easiest way to get aggro is to first charge the clown and then run in a circle to hit all of them, before retreating to a corner and happily blocking out the rest of the fight, occasionally SS-ing for the closest forcemaster add to not grab you. Easy as long as you have HP and blocking skills.
Note: if you have no i-frames available during the room-wide spirit bomb, I suggest dashing  and q/e on the closest force-master add, then returning to corner. Because their rotation resets when Be Ido is bombed by your party, you should be safe for that time from grabs.
You guys have probably the worst luck in jobs… if you have no forcemaster or blademaster, you may have to triple-task!
[Adds] Summoner has priority over blademaster in this job, so it’s up to you to do it first! If you have your cat set to defensive tanking mode all the time, you are good to go. If not, please figure out how to do that— All you need is your cat and a lot of cat-healing. Have your cat rotate between the three adds using Q and heal it to make sure it doesn't die.
[Bombs] Force master has priority over summoner in this job, so get ready to do it if they aren't in the first stack of 10 (this will make sense soon) but if they do, just happily ignore it forever. This job is actually really easy. When the boss is fighting, he will have a fire or ice circle under him. The adds will also have these circles. Stand in the circle that is opposite color/element from the one under the boss and watch your debuffs add to 9 stacks. At 10 stacks, you will have a bomb timer on you. Run to the boss and explode him! This interrupts his buff and HP regen.
[OP One-shot Skill (Spirit Bomb)] Force master has priority over summoner in this job, so get ready to do it if they aren't aka don't trust them and do it all the time anyway. After the boss has exploded, he will form a giant blue globe above his head. The moment this globe grows to max, cast dandelion. The globe will explode as a near one-hit-kill otherwise.
[Bombs] Force master has priority over summoner in this job, so put your skills into the health regenerative side of Ice-F and get ready! This job is actually really easy. When the boss is fighting, he will have a fire or ice circle under him. The adds will also have these circles. Stand in the circle that is opposite color/element from the one under the boss and watch your debuffs add to 9 stacks. At 10 stacks, you will have a bomb timer on you. Run to the boss and explode him! This interrupts his buff and HP regen.
[OP One-shot Skill (Spirit Bomb)] Force master has priority over summoner in this job, so get ready to do it even if the summoner does aka don't trust them and do it all the time anyway. After the boss has exploded, he will form a giant blue globe above his head. The moment this globe grows to max, cast ice flower. The globe will explode as a near one-hit-kill otherwise.
The main thing you must watch out for is debuff stacks. Standing in the boss's melee range means you are in his fire or ice circle. 10 stacks make you into a bomb of the wrong element which means if it explodes, bad things happen. When you see your debuff hitting 8 or 9 stacks, step back outside the circle for 5 seconds to dispel it.
General party awareness should include  seeing if there is anyone with a ticking counter on their head within 1 meter of you -> move away.  Seeing if there is a giant globe above the boss and nobody has ice flowered or dandelion yet -> use i-frame skill.  If the boss force-chokes someone, cc the boss. The force choke will take out the choked person’s health by a lot and regain the boss's hp significantly so disabling is important.
Other than that, dps as much as possible. Seriously. Your OP dps is absolutely necessary because the forcemaster and summoner and blademaster are occupied making sure the other mechanics of the boss are nullified. That means that you need to do about 130% of the work you normally do. Plus if a bombing fails, then you have to do even more work to nullify the ridiculous healing the boss has (he can and will heal to full).
Third Floor: Lightning (雷) God and Wind (风) God: [see Dun's post for more detail]
When you get to this boss room, it will be empty. Walk to the center to activate the first phase.
Phase 1: Wind God Only
Deceptively easy, he uses melee skills for most of the fight. Simply block or dodge if you are the tank, disable and grab or choke for fun, etc. Occasionally he does an attack pattern that begins with a 360-degree aoe. Afterwards, he will send blades of wind at 4 random party members. These blades won't kill you unless you are under 12k hp, and can be blocked, projectile shielded, etc. Then the boss will generate this boomerang-shaped wind as a linear frontal aoe – it can be blocked or dodged, and if necessary, use i-frame. The boss will then do some charges (kind of like the ones from the twins in Bloody Shark, they knockback) which can be blocked.
Phase 2: Both Bosses!
If your party has barely passed the previous two bosses, you will most likely split 3/3. If your party breezed through everything, you might do the bosses at the same time in the middle. The 3/3 split is safest and most recommended/popular. Note that if you kill one, you have 30 seconds before the other enrages.
Typically, each side will have a tank, 'protector/projectile shielder' and 'grabber' for optimum split.
The wind god has basically the same skills as before, but with some added tornadoes floating around. Avoid them, as they toss you into the air and can disable you indefinitely if unlucky.
The lightning god side tank basically just needs to block all his frontal aoe, and sometimes make a rectangle of lighting on the ground (just avoid it). Similar to the tornadoes from the wind god, the lightning god will summon balls of lightning that shock/daze you. If a tornado and ball meet, a lighting pit will form that continuously damages anyone on it.
Every minute, the lightning god will cast an aoe on the whole room that can't be blocked (a red circle will sweep the entire ground to warn you). Raijin is cc-able during this AoE, so you can do that to stop it from going through. Otherwise, it isn't a one-shot by any means, so feel free to just get back to dpsing. The only disadvantage is that everyone including tank will be knocked back and therefore get pulled in and hit 4x + groggy. Feel free to ice flower or dandelion here, if your party doesn’t i-frame it themselves.
After the aoe, the bosses will 'link' together (as shown by a thin band of lightning between them) and slingshot tornadoes, then lightning balls, at 3 members then at furthest party member respectively. They can be projectile shielded (or blocked, but typically people are facing the wrong way). Finally, after the lightning ball the tank of Fujin will be pulled by Raijin, so the tank needs to dodge that. The order of tornadoes -> lightning is reversed every other round.
The boss timer for these two is quite nice, and ever since HongMen levels were introduced I don't think any party I've been in has taken more than 3 minutes. The timer is 6 minutes iirc.
As a note, if you cannot keep the two boss HP's even it is preferable to kill Fujin first, because Raijin's enrage is merely dropping lightning like Hae Mujin does clones in BSH, whereas Fujin's enrage is eternal knockback AoE's like Bloodmane. If you do end up with eternal knockback, place yourself with back to a wall so that the knockback hits you but does not have the full cc get up effect that requires you to get up. This way you can maintain dps and have more time to prepare the next iframe.
Feel free to ask questions or clarify things below. (And if you think this guide was helpful, I'm willing to accept reputation points >.>)
Edit March 09, 2016: More details and conditions (eg. post-enrage) on the last boss.