Easy Leveling Guide
Written by MSG Commander
For fastest results, I strongly recommend that you buy the EXP Orb in the Online Shop. (Especially if you're playing the Premium version and have the free points to spend anyway.) The EXP Orb is not an essential part of this plan, but it will speed the process up immensely.
When to Begin
You can start to grind at the beginning of the game if you want to. Just put the Difficulty on Hard. (Don't start on Expert unless you like to suffer needlessly...)
But realistically, all this will accomplish will be to make the battles more challenging, and the game take several hours longer to complete. That in itself is not always a bad thing - but for this guide, I'm assuming that you want to finish the game on Normal Difficulty, and then grind to 999 after the story is done.
After the Normal End
As soon as you finish the Normal End, go to the Forgotten Village and get two of the Maid Weapons in the basement of the Inn. (I recommend Maid Brand for Izayoi and Laundry Pole for Freya, but any two will do.)
Equip these two weapons and transfer any effects you want. Also, equip all the First Rings, Parameter Rings, Break Rings, and Weapon+ Rings that you have.
Now, set the Difficulty on Expert, and turn the Battle Shortcut on.
It's very likely that you will skip most random encounters now in all four magic fount areas - and the ones that you do have to fight, you can probably Auto (unless there's a metal monster, then you'll have to use your regular physical attack and try to get a Critical hit.)
For Boss battles, set the Difficulty back to Normal, or, if you want a bit of a challenge, fight them on Hard. (If you fight them on Expert, you're asking to have your you-know-what handed to you, unless you really know what you're doing.)
The two Maid Weapons will make your team powerful enough that you'll be able to handle almost every random encounter with ease, and by the time you're done you'll have gained an extra 20-50 levels (depending on if you have the EXP Orb, or an EXP Ring, or nothing at all.) Not much, I know; but, with the Battle Shortcut, skipping to the result screen takes the same amount of time regardless of your Difficulty - so you might as well turn it all the way up!
Plus, it'll make the beginning of the "post-True End" grinding just a teensy bit easier.
After the True End
After completing the True End, you'll have another 3 Tray Gems, so go get a third Maid Weapon (and then you'll have to farm Tray Gems for the fourth one, but you can do the rest of this guide with just three Maid Weapons, no problem.)
To Level 600
Once you have the Maid Weapons, put the Difficulty on Expert and go to Metal Isle B (south of Yggdrasil, west of Metal Isle A).
Save your game, equip the Encounter Ring, and start walking around. You'll have an encounter with each step, and within about 10-15 minutes you'll be Level 600 (it might take 20-30 minutes if you don't have the EXP Orb).
You can also equip one or more Metal Arkstones, Big Arkstones, Leader Arkstones, etc., but I'd stay away from 30 Arkstones, because you'll probably skip to the results screen straight away, regardless. Plus the metal monsters here have quite of bit of HP (especially on Expert), so the 30 Arkstone may not be all it's cut out to be.
To Level 999
Now you have a couple of choices. If you just want to get to 999 the easy way, stay on Metal Isle B for another 20 minutes or so.
Or, if you want more of a challenge, take off the Encounter Ring for a minute, and hop in your boat and sail to Fairyland (very small island east of Mapel Village.) Put the Encounter Ring back on, and temporarily reduce the Difficulty level to Normal (then Hard, and finally, when you're ready, back on Expert.)
Individual battles in Fairyland will take much longer, but the EXP and Gold rewards are far, far greater. (In ONE battle on Expert mode, I got over 17 million EXP, and 5 million Gold - and went from Level 641 to 655.)
If you do choose to go to Fairyland, make sure you Save your game after every battle! (It's always better to be safe than sorry.)
If you come to Fairyland around Level 600, and adjust your Difficulty to your liking, you can either Auto the encounters here (although if you do that, you might as well stay on Metal Isle B), or you can actually use a strategy to defeat the mobs. For more details on this, see "Fairyland Domination!" in the forum.
This guide is only for grinding to Level 999.
If you want to farm various weapons, items, etc., you'll have to visit more of the "unmarked" locations (places like Barrel Region, Boulder Region, Level 300 Region, that exist in the game, but are not marked as such on the World Map.)