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Disgaea 3 Power Leveling Maps.
Practice Map Edit
Throw the XP+50 block onto blue, and let the prinnies come onto the blue panels.
Map 1-8 (Strongest Crossroads) Edit
Five Prinnies and three Orcs in a section of +50% Exp / +50% mana. With decent area attacks, this map will take three rounds at best. It will take longer if you don't kill the enemies before they move.
Map 2-1 (Childhood Memories) Edit
This one is a little tedious but really great to get up some levels early on. The way to play this stage is to combine the enemies together by throwing one into another. By making sure you throw all the characters into the Cleric enemy you'll have a high level opponent that can do virtually no attacks. On top of that almost all the fighting takes place on +50% experience blocks. Pass the "Stronger Enemies" bill twice and the majority of the characters on this map will be level 12, if you then combine them all into the Cleric she'll be level 70 some, kill her twice with a level 10 character and he'll be level 35 or so. Beware that the weak warriors will attack your troops who will then counter-attack and then one-shot them before you can combine them with the Cleric so be sure to set the map up using troops that don't counter (Clerics, Clergy, Mages, Witches).
For higher levels just keep passing that "Stronger Enemies" bill. It may be tedious but with this method you can pretty much level up any character type without fear of them getting killed since the Cleric is so weak. This is probably the safest fast way to level before getting to the speed leveling map in chapter 7.
Map 4-3 (Eternal Teardrop) Edit
This level is similar to map 4-3 of Disgaea 2, having a decent number of enemies standing on Enemy Level +10% bonus tiles. Unlike that level, however, the map is entirely composed of those tiles, is paired with movement hampering effects, and has geo blocks on the far side of the map rather than being nearby. You can let the monsters level to a bit below your target level, then rush the stones to stop the leveling and kill the Warslugs on the way. By the time you clear the stones, the rest will be at your target level or a bit higher, and weaker thanks to the geo cascade. Start this with no SEBs passed however, to reduce the SP the Warslugs have and minimize the damage you will take from their area attacks.
Stacking and throwing allows you to effectively move across the map. On the first turn, stack your team next to the first Warslug and take him out. On the second turn, move towards the blue block by throwing your tower and then moving the thrower back onto the stack. Be sure to note how far each character can move before throwing and remember that your movement is reduced. When the Warslugs are at your target level, destroy the blue block. Optionally, you can kill the Vodianoi first then let the Warslugs level up a few more times before destroying the blue block. Warslugs won't attack unless you are within a certain range. Throw your stack to a position where it can take out one Warslug without getting aggro from others. Since Warslugs have strong magic but weak defense, a tower attack can take out Warslugs that are 10 times the level of the characters.
Map 5-2 (Organized Corridor) Edit
This map has an Enemy Base Panel that will pop out a Succubus every turn until the 10th turn. The first go through of this map has a Fusion, but on repeats it has XP + 50%.
The trick is keeping an enemy alive at the end of every turn until they stop coming out of the enemy base panel.
Alternatively, if you use "End Turn" to execute an attack that, in turn, kills the last enemy on the map, a Succubus will still pop out of the Enemy Base Panel at the end of every turn, despite the map having technically been cleared. However, if the team member currently being boosted does not 1-shot the enemy in question, it has a high(er) risk of dying to potential counterattacks, which WILL trigger the "Stage Clear" if it does happen. Slightly faster if you can 1-shot everything, but slightly riskier if you can't.
Try keeping the member you are leveling in either the corner club or punk club to maximize XP or HL gain from this map.
You may have to pass the stronger enemies bills for this map to be effective at higher levels.
As you get stronger, it is suggested that you start by throwing one or two of them together so that the new monster becomes a lv.60 and then continue fusing them as needed. If you fuse them all(counting enemy reinforcements), it should become a Level 450 monster(no SEBs passed)
Map 5-5 (Rotten Grudge)Edit
Though there are not any XP + x% panels, this is a good stage for leveling your characters, the low-leveled ones as well as the higher-leveled ones if you pass the "Stronger Enemies" bill.
All you need is a character to tank the zombies, a healer, and a ranged fighter (archer, mage, etc). You'll see that you have two big, high platforms in this stage, connected by Geo Blocks that result in some form of a bridge. As you can see, this "bridge" is 4 blocks high. All you need to do now is take the ranged fighter and destroy the second block so that the tank can lift the first block, which is no longer connected to the others of the same color, and throw this block onto the others. After the first chain reaction, only 3 rows of blocks are left. End turn. Repeat these actions to destroy the second row. For the third row of blocks, have a character jump off the platform, into the hole the destroyed block created, and throw the Geo Block onto the others. Now only the yellow blocks are left, and it recommend to not destroy them because they give +50% Mana. Now you take the character you want to level up. For the ranged character, place him right behind the tank. If the character is a melee fighter, let the tank lift him/her until he/she can survive on his/her own. Now the Zombies will come over the bridge after the few turns. Before they arrive, put your healer on the border of the high platform to heal your characters when necessary.
This is an easy stage to level up on, because the enemies only have one way to reach you and are melee fighters. Also, your healer just has to heal one character while you are leveling.
This level is also ideal for the Level 99 glitch trick. As you face 9 zombies, all of whom are Level 33, you can throw them into each other to create 3 level 99 zombies. Killing each of these zombies will result in incredibly high amounts of exp.
Map 6-1(Evil Mind Vortex)Edit
10 White Dragons on big towers of Enemy Level Up 10% grants some seriously high level monsters. Let the towers level up the dragons sufficiently then just throw the nearby Geo Blocks to stop the mayhem and also greatly weaken the Dragons (both in terms of HP and statistics thanks to their evilty). Just mind that you don't let them level up too much, or you may regret it. Can easily get a level 30 Mao with decent equipment and specials to a much higher level(as an example of how this can be used earlier rather than later).
Map 7-3 (Corpse Eaters) Edit
After clearing the map the first time, you will find XP+100 and enemies in a 3x3 pattern. This is the map you need to have a fully upgraded fire, wind, water, or star spell to take them out in one fell swoop. (Big Bang also works if you have that skill.) Its the third best power leveling map in the game. Pass the stronger enemy bill 4 times and you will have level 99 mobs that give XP based on a level 320 - so abuse this map. This map works well until level 500, by that time you should be able to abuse Hall of Ordeals 4.Also if you cant get the Hall Of Ordeals you can keep doing Stronger Enemies bill and they go to Level 250.
Hall of Ordeals 2 Edit
8 level 200s on a +100% XP geo panel. Using leveled giga magic or good area attacks, you can clear it in 2 turns. It's good up to level 400; the "stronger enemy bill" makes the boost even better. Combine it with the Corner Resolution group for another +25% XP and put some honor student group members around them, and you're good to go for a long time.
Hall of Ordeals 4 Edit
This is by far one of the best leveling spots. As long you have Big Bang (or any Omega spell that has been upgraded 8 or 9 times), and well leveled, top-notch gear, its possible to get well over level 5000+ on this map if you use the stronger enemy bills to the max. XP+100% and 9 enemies on a 3x3 alignment is ripe for abuse on any level.
To get to level 9999 in 2-4 fights, go to LoC with capped Rank 39 or 40 equipment, and have 8 300 statisticians on each item. Depending on the character classes being levelled up, classes like the Male Fighter take only 2 fights with a stack of 32 statisticians while the Majin class can take 4 or more fights to reach level 9999.