Transitioning Tiers: a Tale of Tears.

Me and a buddy just made the jump from Tier 2 to Tier 3 - we just whacked the Jelly King, alchemised our 4* gear (Ash Tail swagger, aw yeah), and finally got access to Emberlight. Wandered round being tourists, looking at the town's outcast Gremlins, good times.
Then we thought "Hey, let's take a peek into the Tier 3 levels now that we're here."
First Infernal Passage level wasn't so bad - sure, the monsters are a bit tougher and do more damage, but with careful play and frequent shield use that's survivable. The Ultra Capsules helped a lot too.
"Hey," we thought, "this isn't so bad. And what's that on the gate map - Stygian Steeds? Sounds interesting, let's try and check it out!" So we strolled onto the elevator, pretty sure that we had things under control.
And that, dear readers, is how we ended up lying beaten, broken and thoroughly humbled in the first Dark City mini-arena area while monsters trampled our corpses. Damn you, Kats. Damn you, Devilites.
Previously we'd had a pretty good system going, mainly sword and shield use (Calibur and Defender lines) with a bit of Graviton Bomb action from my esteemed associate. We'd take turns kiting enemies around while the other unleashed charge attacks in their midst. Tier 3 took our previously-successful tactics, rolled them up and spanked us with them. Hard.
My question is thus: How do you make the transition from Tier 2 to Tier 3?
What did we do wrong? What are vital things to take on a Tier 3 expedition? What's a good loadout, what are good tactics? How do you deal with hordes of foes whose every attack knocks off ludicrous amounts of health?
Answer: Don't do it on a T3 devilite level. Those levels are absolute murder. I have a decent selection of 5* gear and the little cheaters will melt your face. A shivermist will probably be the only hope in those phone booth brawls to keep the throwing objects down. The rest of the time it's flourish/avenger and drop your shield down for only that split second to get off a single slash. Play some of the other T3 levels. I'm more scared of the 2 foot high devilites than I am of Vanaduke.

This is what I did back in the day I mean AGES and AGES ago:
I was lucky enough to find a guild with some pretty great experienced players and I did runs with these players. I ended up getting owned about 50% of the time since I was pretty newby at the whole game at a given point and time, but after doing a few runs with them, and attempting to just practice a lot in T3 I am able to do majority of all the T3 Maps solo'ing to the core (Besides Vanna Maps I can not or well I have not attempted to solo Vanna). My suggestion is to either go in T3 find an easy map you and your friend and attempt it do not revive yourself more than once. This game is a lot of practice once you learn the attacks of monsters and figure out the best strat to kill them you will master this game easily. Like your parents and coaches might of told you before Practice makes perfect. I do not think you did anything wrong at all. I usually deal with hordes with using bombs if I solo I freeze then sword them or just nitro or ash it up. If I feel like having fun I use either my DA or Gf and own them all. Also, having the right gear helps out I have a few sets of gear which helps me be prepared for all kinds of maps.

@ Elegies
Yeah, the Graviton Bomb just doesn't really have a big enough area of effect to work very well in such situations. Also, apparently it has a long charge time (at least until my esteemed associate gets some Mad Bomber gear), which limits its usefulness. We'll definitely be taking it slower next time; previously I'd let myself get mobbed while charging up an Ascended Calibur attack, but with each monster dishing out so much pain per hit... yeah, not worth the risk.
@ Frederf
That... explains a lot, actually. The jump in difficulty from the first T3 level to the second seemed pretty spectacular, and now that I think about how Devilite levels compare to other types in T2, I begin to understand. Those office supplies really hurt.
@ Njthug
Yeah, there was a bit of rage-reviving at first, and running around reviving each other... but when we were both knocked out for the second time there was a mutual agreement that it just wasn't going to work, no matter how much CE we threw at it. So, no more Fiend strata until we've thoroughly heated up our gear and polished our tactics. Crowd control was the big issue - just way too many monsters to take on at once.

Well what I do suggest are more:
Gremlin base tiers, the regular lumbers etc., and jelly's are pretty much easy. Shock and Fire levels are pretty tough so I would stay away from those. Freeze level with a partner can still be tough but doable.
For Gremlins in Tier 26+ They do get to be tough bombs are needed against them for great mob controlling.
To be honest, I find Firestorm Citadel and Vanaduke easier than Fiend or Shock stratums.
A) Get better with your shield. And get a better shield. Learning the mechanics of Shield Bouncing is a necessity. Getting a feel for how long it takes to get your shield up and how long it takes to drop, also a necessity. And more than any of the above, learn that you CANNOT land your full sword combo and then shield. You cannot get the last hit in, before T3 enemies lash back. (If you get the Vog Cub set, you can. But prior to full Vog Cub, you cannot. So stop trying.)
B) Learn proper Aggro management. Some Aggro tactics work in ALL MMOs, and it shocks me to see how many people in this game have no idea how to Aggro manage. For example. A Gun Puppy is over on the side, spraying the arena. Proper Aggro Management, is to go behind it, get it's attention, and kill it from that side. That way, it's spraying AWAY from allies, as you kill it in the face.
Or, look at Trojans. It can only be attacked from behind. Proper way to fight one? Figure out who has his attention. That team mate shields and dodges within a 90 degree cone. That way, the other teammates can POUND him from behind. Once he turns, everyone spreads out to their own 90 degree cone, quickly figures out who has his attention, and then wails on him from behind.
C) Learn about enemy mobs. With Devilites, you need to take out the bosses and the Yesmen. Sure they don't attack; but once they die, the other powered up mobs de-level into softer-hitting mobs.

Problem is you were fighting Devilites and Kats. Both of which are the primary enemies in Dark City levels... which is also why A LOT of people avoid Dark City levels. Both move very fast, attack very fast, and in the case of the Devilites, their projectiles move very fast. Oh, and Devilites have a tendency to dodge gun shots also.
Dark City also ups the difficulty even more by sticking you in a smallish rooms with the mobs. Reducing your area to dodge the 10 or so enemies that all spawn at once.
I actually did the area you're talking about, I had never seen the Stygian Steeds floor before and figured it would have a ton of Trojans. "Stygian (aka extremely dark, forbidding) Steeds"... Trojans... the idea made sense to me. Much to my dismay there were exactly 2 Trojans, both in the final party button room of the floor.
Honestly, if that was your first real Tier 3 run, and you got down to floor 25 without dying until reaching the Dark City floors I think you did rather well.
~Gwen
That way, it's spraying AWAY from allies, as you kill it in the face.
Oh my god, can we be friends all the time forever? If not, that's cool, but we should play games.
I friggin hate when I end up in a random party where the other knights pull the aggro from EVERY DARN GUNPUPPY in the room!!
Kepp close to the walls when a wave of enemies die, so that any eventual Gunpuppy wont se you when they spawn.. Then hack away at its back.. follow the wall and repeat on the next one, and the next.. and so on..
About the other mobs.. that have already been stated above :)

@ Npasq
Thank you very much for those tips, I'll definitely be bearing them in mind next time round. I'm pretty practiced in clearing some space with a shield-bounce, but when there's no room to bounce the monsters to... that's when things fell down.
@ Gwenyvier
I think we died a couple of times in the Jelly King's throne room, but we've been grinding T2 for long enough that it's not too much of a problem. Mostly it was down to slipping up and getting pinned by the Jelly King or swarmed by the smaller jellies, and we revived each other and carried on.
It was only when we got to the Dark City that we felt horribly outmatched. Previously it was a challenge, but a surmountable one. The Devilites and Kats were just murderous.
Dark City in T2 still kills me. I avoid those like cilantro unless I've got a skilled bomber in my crew.
In my experience, T3 isn't necessarily more difficult than T2, it just takes more time. I'm sure you've honed your soloing skills in T2; apply those in T3 whether you're soloing or not. Draw individuals or smaller groups out of the crowd, shield-cancel, kite, etc.
i just couldnt stop laughing...mister OP ur damn hilarious...
anyway i didnt move to T3 until i had my 5* sword and a 5* pice of armor....and i just take everything reeaaaaaal slowly to ensure survivability
once u get to vana's lvls just let the wheels kill everything....

Ugh, I remember how brutal Stratum 6 Fiends was on my first attempt at Tier 3. Despite having a party of four we had to energy revive to get through Depth 28 Plazamonium. Ow.
I swear the Kats in Dark City exist solely to get in your way while Devilites bombard you with chairs. :x
Oh yeah, and the Flourish lines are good at separating Devilites from their bosses, and can sometimes allow you to take out huge mobs of them without getting hit if your party can distract the others. They're also really good on Kats, but mine has UV on Undead so that could just be me. :P
The Defender line of shields is not so great. Only one kind of monster has a piercing attack, so half of its defenses are straight-up wasted on anything that's not a merged Lichen Colony... or a spike trap, I guess... If spiketraps are a primary source of damage against you, you probably have other things to worry about.
Owlite looks ugly until 5*, but has valuable status resistances and Elemental defense.
Skelly shield is, well, undead themed so it's not everyone's cup of tea, but has Shadow defenses to help you stand up against Kats and Greavers.
What kind of armor are you two using?
>What kind of armor are you two using?
They're using Ash tail gear, which is great for T2. In T3, however, the big gaping elemental hole you have will likely get you slapped silly by everything under the sun, especially laser bots and puppies. A single piece of norm/elem armor makes a world of difference.
My suggestion echoes the people above: it's possible to go down to the core in 4* but it takes some massive cherry picking. For now, try doing lower stratum T2 danger rooms, which spawn T3 mobs to practice in a "safer" environment, and the mechanized mile type of levels (probably not the fire/shock ones though), which give you a steady stream of mobs in manageable chunks.
I find the Shivermist bomb to be far more effective in T3 than the Grav duo.
More generally, with T3 herding doesn't work nearly as well (imo). It's better to try and separate/pull one or two mobs from a group (kiting for a long time, if needed) and pick them off one by one.
You want to make sure you have a good coverage for the different foe resistances. Defense against elemental tends to be very helpful.
The biggest thing is just to SLOW DOWN. Rushing through T3 is something that people who have done endgame for a while can manage, but just starting out is very difficult.
You'll notice things get markedly less "unfair" when your gear is 5* and nearly maxed in heat. There are still some things that will be unfair though, like gremlin levels with mines/flamethrowers covering the map, and the always-dreaded quicksilvers.