Let's talk about descends with numbers.
Descends are ways to acquire power monsters, but the difficulty of descends are unimaginable. There are guides all over the internet talking about how to build a team for which descends - which I'm not going to repeat those here. What I am going to talk about is a history of descends in PAD, and how are they evolving.
Let's get started by this list of descends, from the old to new:
Before we go ahead I would like to introduce you some terms I am going to use:
DPS - The average damage you are doing per turn, or average damage you are taken per turn. DPS of boss also means the healing you need per turn to sustain you HP. This idea is very important on choosing your member of your team, although your healing varies by your skill, number of heart orbs appears or others, but this number should give you a rough idea on the difficulties of the descend. Stole this term from most MMO game because I don't want to make new abbreviation.
Largest Hit - The biggest number you will take on that floor. This only accounts for hits that you are suppose to take (not the 430k damage that are mean to one-shot you).
Enrage - Significantly increased in DPS when the HP of the boss is lowered to a level.
Mechanism - Different skill used by the boss including shields, orb change, binds etc.
Now let me categories the list.
Hera, Two-heroes, Zeus, Valk, Goemon are Type I descendsThe common set up the Type I descends is that, they all have floors that let you stall for skills. The DPS of those floors is high, but you can lower the damage by killing some trash mob on the floor. Examples are the knights and demons in Hera, ninja's in Goemon. To effectively stall on these floors you need to kill some but not all of trash mobs, and carefully match orbs to get enough heal and not too high damage to kill them.
The other common set up is that there is a mid-boss floor that serve two purpose:
1. Make you use your skill so you have less tool when you face the boss, and
2. Let you stall.
Examples are Mitsuki in Goemon and MKIII in Valk.
Hera-Is, Satan, Zeus-Dios, Hera-Ur are Type II descends
These four are the worst descends in PAD history.
They are hard. Just plain hard. Everything tries to kill you in one single hit.
You got basically first floor to stall for everything you need and you got boss rushes from the 2nd to 5th. There are heavy preempt strikes that needed to take care. They have preempt shields that put Echidna out of your regular team member.
The conventional way to do these is a high multiplier team. Horus, Ra, Kirin, Ronia, DMeta. Just burn everything and hope you aren't getting orb trolled. This is the descend which makes people think DMeta is great. In fact she is not. fucking. viable. in late game! If you plan to do type I and II descend forever, go and feed 297 to your DMeta and roll like crazy for Hanzo.
Starting from Athena, up to Hera Sol (the most recent one as I am writing this) are Type III descendsThey are boss rush, and in terms of stalling, you could do that on the most comfortable floor depending on your team. But each floor has a mechanism that tends remove, or bring difficulties to one type of build from the face-roll list. Type III descends focus on annoying skills rather than just OHKO you.
You can always find few of the following mechanism to stop teams that do not need to puzzle from face-rolling.
1. First floor oneshot to stop 414 team, especially SoD Lucifer.
2. Preempt heal+oneshot to stop team that require <100% HP, like Goemon and DMeta.
3. Heavy preempt strike+damage per turn to stop multiplier that require 100% HP, like Zeus or Izanagi.
4. There is always a mid-boss that oneshot you in few turns to test your team DPS.
And there are three new mechanism introduced in the newer dungeons:
5. Reduced orb matching and constant orb change to hinder combo team.
6. Preempt skill block to stop Sonia and DMeta from press-skill-and-win on the first turn.
7. Combo shield to stop heavy row enhance team, again targeting Sonia and DMeta.
Now let's talk about numbers.In fact it is hard to get everything in a analytical way because of the random nature of this game. I will leave out the trash mob parts and mid-boss part, and focus only on the "number" of the bosses.
Take a look at the HP of different bosses.
Most bosses have HP at around 1.8m except for Takeminakata (tri-color) and Valk (seriously why she has so high HP in Legend?). The enrage HP is the mark of the highest burst you should do because most boss during enrage oneshot you. A shield works to buy you one turn (kushinada) or 3 turns (golems) or 5 turns (susano).
But solely look at the boss HP does not reflect anything.
Let's say I use a spike team and decide to melt the boss before they can touch me. Surely I bring my lovely Echidna for a 3 turn delay so I have enough time to kill them. Now take a look on the DPS I need.
For type III descends, some of them have preempt skill locks that you can't just pop Echidna and start killing. Luckily the skill locks are short and they don't recast. But you still need to survive without skill over that period of time.
Talking about survivability, let's also take a look at the DPS of boss (aka the healing you will need per turn).
What? "You sure there is no typo"? Surprised by the drop of DPS at Type III descends? Have you ever think of how to take one hit from Hera-Ur when your Echidna is not ready without dying with your burst team? Why Type III descends has so low DPS? Are they that fucking much easier?
This probably related to the history of available gods.
During Type I descend released, the popular team team we have is 2/4/2, or Zeus 9x but HP restricted. With a 2/4/2 team we can easily hit 25k HP and 5k RCV. Now take this in mind and suddenly everything within Type I descends make sense. They have high damage per turn because your team halves their damage (2hp&2rcv = 50%damage reduction). We don't have skill up material so there are floors that let us stall.
And now high multiplier team kicks in. The Egypt god, 3x multiplier on Type, Skilled up Zeus 9x with two inherit gravity plus descent light team member. Here's are the Type II descend begins. Since high multiplier is facerolling Type I descends, they take the descend to a even higher level. "Yeah you like oneshot? Fine."
Type II descend has gotten to a point where 2/4/2 didn't really work because you don't have enough RCV to survive. Zeus didn't work because of heave preempt strike and shields that stop you from using Echidna. All you need to do a make a 9x or 16x team, put a King Slime, and melt through everything. These are the worst days in PAD history because people without high multiplier can't do any of these dungeons (keep in mind there was NO awoken skill and ultimate evo that tackles binds etc).
Now the descends evolve into Type III, where boss has low damage because people like spike team - and they adjusted the damage so that spike team can actually heal up themselves and survive a few hits from bosses. Does that mean 2/4/2 can faceroll the descend? No. There is also a floor that check your burst DPS. Burst DPS is the weakness of 2/4/2 - it is hard to deal large amount of damage in short time frame. But hey row enhance helps, orb change helps, the twin dragons helps! But you need to prepare for this. Does that mean spike team (combo team and Egypt god) still faceroll Type III dungeons? Hmm, my team - yes. What can kill me with 4.5k RCV and 2 heal skill + 2 delays? jk. Jokes aside, the orb changing and damage absorb is frustrating but not lethal. Hey they can be solved by YOUR SKILL rather the monsters active skill.
Type III descends focus on mechanism to deal with rather than a very short frame of burst you needed. They just use every mechanism to stop you from bursting them down in the first turn. What you are doing is heal and kill. You will be annoyed with skill lock, damage absorb (especially dark), per turn binds, random orb change, jammer and poisons, combo shields etc. In fact if your team is not an extreme spike team that have low RCV (by low I mean ~2000), depend heavily on skill activation and row enhance and extremely susceptible to mechanism, these dungeon is a bliss for you because you can actually feel the puzzle part of the game, heal, and attack.
Also the largest hit of the boss also falls significantly from a oneshotting ~16k down to manageable 10k as a team in Legend level. There is also a grace period before the enrage phrase of Type III dungeons so you can prepare for a large hit. Back in time where I am doing Celestrial Pole and accidentally lowered Leilan's HP to 15% and she hits you for 63k and I say "wtf skyfall fucking please stop now", this is a very solid change to the game to remove obsolete and frustrating mechanics.
I'm not forcing anyone to abandon their team
So what are you trying to tell me?
1. New mechanisms will be introduced from time to time. If you think they just annoy you then your team is good. If you can think up of a mechanism that specially kills your team, you should start prepare a new team, now.
2. Team that faceroll by pressing skill will be harshly blocked. If you still plan to roll that Hanzo for DMeta just for descend, prepare to get locked 3 out of 4 descend because apparently YamaP doesn't like this.
3. RCV > ATK
3a. HP is also important, as a buffer to heart orb trolling, and in extreme case, soak one hit during enrage
5. Can I do X descend? Just ask yourself if you can pull up 5k heal consistently for a few turns without skill. 10k heal for Mythical.
Last of the least: Mythical data - for those planning to do Mythical.Boss HP
Average DPS required
Average healing requied - How can I not say RCV is extremely important?