In the event the video goes down or you prefer a text guide, more below. The video actually goes into too much detail; by the time you get to the stat maxing section at the end, you will likely have all difficult achievements completed.
Items max out at level 300. In order to do this, you will need an item of Legendary quality and at least 10 Mr. Gency Exits. Personally, I would recommend doing this when you get rank 41 weapons and armor, as you will want to do this anyway for Baal. As a general overview, every 5 floors in Item World, you will have the option to choose Item or Innocent Boost. ALWAYS
choose Item Boost.RECOMMENDED CHARACTERS
To clear the Item World efficiently, you'll want a runner. Create a high-tier Bouncer and put them in the Aura Pyramid to get some mana, then teach them all fist skills, but most importantly, Big Bang. Optionally, take them through Chara World to gain extra movement. Level them up through Mt. Ordeal 4, and preferably when they're 9999, reincarnate as a Masked Hero. Teach them the Chicken Heart Evility and you should now have 11 movement even before movement items like Accelerator, Propel Vernier, or Barefoot X. Once they've moved 10 tiles in a turn, you can unlock the Nether Express symbol, which, if given a non-impeded path, gives the ability to establish a warp station, giving your damage dealers significant range.
You'll also want a thrower. Again, create a Bouncer but only teach them Big Bang. Take them through Chara World for Movement and Throw Range bonuses. Reincarnate as a Heavy Knight. After a few levels, the Heavy Knight learns Lift Catch; boost this skill and your thrower will have a large lift radius.MIN/MAXING
Before starting, load up six single stat boost innocents of your choosing (Dietician, Master, Gladiator, Sentry, Tutor, Physician, Marksman, Coach) as they will be used to get bonuses in their respective stats for killing Item Leaders. This isn't necessary for the achievement, but will make for a stronger item and will be crucial when leveling later items for end-game achievements.
The only change in this strategy comes at floor 30. When you kill the Item Leader and Gency out, the innocent population max increases, so load up a seventh stat booster. Kill the Item Leader again and leave after Innocent Town's bill to load up the final stat booster.GENERAL STRATEGY
Use your runner to quickly enter each portal, using Triple Strike or Exploding Fist to move gate keepers, or Create Station to bring a damage dealer in. Go down ten floors and kill the Item General/King/God, then Gency out and save your game. When you re-enter, you can kill the Item Leader again
for a continued boost and a few extra levels. On floors 10, 20, 30, 40, 50, and 70, if you do not reach Innocent Town, or Innocent Town does not have the Cam-Pain Eryngi, quit and reset. You'll want to propose bills every time you can to power your item up further. For weapons, I suggest Attack Range; for items, I suggest Movement.
Gency out at Floor 99 to begin the Reverse Pirating stage.LEVEL SPHERES
Starting around floor 20, level spheres will begin to appear. These are worth 5 levels each. To redeem, you need to be lifting them while the stage is cleared, either through defeating all enemies or entering a portal. Anyone can lift, but your thrower can use Lift Catch to pull them to him.MYSTERY GATES
If there are no level spheres, feel free to enter a Mystery Gate to reset the level. Additionally, there is a chance you will run into the Augur. Talk to him and he will divine the item; if it's good, you've gained a couple of levels, and if it's bad, you'll lose that amount. Talking to him repeatedly afterwards will trigger a fight, and winning will add a few levels. It's up to you whether you want to reset on bad fortunes, but I would definitely reset on "really terrible."
Here are some numbers to aim for when traveling through. If you don't think you'll hit these numbers, reset and try again.
- Floors 01-10 - 0 Spheres - Level 12
- Floors 11-20 - 0 Spheres - Level 24
- Floors 21-30 - 2 Spheres - Level 46
- Floors 31-40 - 2 Spheres - Level 68
- Floors 41-50 - 2 Spheres - Level 90
- Floors 51-60 - 3 Spheres - Level 119
- Floors 61-70 - 3 Spheres - Level 148
- Floors 71-80 - 4 Spheres - Level 182
- Floors 81-90 - 4 Spheres - Level 217
- Floors 91-99 - 4 Spheres - Level 250REVERSE PRIATING
Now that you're at 250+, the final levels will come from reverse pirating. By now, you should have defeated a pirate and passed the Pirate Editor bill. Create a pirate ship of your own, prioritizing Total Stay Turns and Total Crew. You can reverse pirate on every 20th floor, so you'll have four floors available.
Once in, there will be yellow and red level spheres - these are worth 10 and 15 levels, respectively. In order to cash these in, they need to be thrown back to your ship before the last enemy is defeated or the last turn is up. If you were over level 250, you should be able to get the achievement reasonably quick from here.MORE MIN-MAXING
Because we stopped at floor 99, we can continue on. Finish level 99, then face the Item God on floor 100. From here, you can kill the Item God, get your stat boosts from the single stat boosters, and Gency out indefinitely for a bonus on each kill, requiring only a Mr Gency's Exit for each loop. The only efficient way of getting Mr Gency's Exit is to buy them in the Land of Carnage, and that is only available after you defeat Baal for the first time, so this isn't an option during the achievement run.
HL grinding is done in the same manner as Mt. Ordeal 4. Get Big Bang on Artina, then give her the Evilty for 100% HL drop on killing blow. Load up armor with tons of Brokers, set the cheat shop to 1000% HL and max level enemies.