Record of Agarest War

Tips to making this grind just a little easier. Since the recommended party is the five main heroes and Dyshana, you'll have a lot of physical power and limited magical power. This can make it difficult when certain enemies get to 25% health and dodge all physical attacks.

If you can gather enemies in a close proximity to each other, you can hit them with your EX Skills, which will hit them regardless of what abilities your enemies gained. Try to get your enemies clustered together so you can hit more than one with your area-of-effect EX Skills. The following EX Skills have AoE:

Leonhardt's Howling Blade (EX1).
Ladius' Rush Storm (EX1) and Blaze Storm (EX2).
Duran's Cluster Shot (EX1).
Rex's Force Blaze (EX2).
Dyshana's Dark Blow (EX1).

For leveling up, I found Reluctance and/or Poverty the easiest until you're about level 350. Both of these are located at the upper left of the Boundary Plane, after you've . At level 350, you're the same level as the enemies, and you're no longer gaining a lot of experience.

At this point, I leveled up at Devilsbane, which is at the far middle left of the Boundary Plane. Here you fight a powered-up Deeth, Musaka, and Casibal (both from Gen. 1). At level 350, you can usually end the battle by Turn 3.

Since you'll have mostly physical-based party members, you'll need the following combo skills, and many as you can manage. The Combo-Skills you want to use are Execution (Double Edge+Cross Edge+Square Cross) and Gore Crush (Power Attack+Meteor Impact+Deadly Blow). Do NOT let those two attacks combine into Cruel Force, because it does significantly less damage than Execution and Gore Crush on their own. Hit them with about three or four Executions, have Dyshana use one move, and then two or three Gore Crushes. This will kill each enemy in one turn, for a total of three turns.

The reason you want to fight this battle is because all three enemies have the Fighter AI, meaning they'll go for the closest party member and not retreat (like Mage AI), or circumvent your front liners (like Thief AI). This makes it very easy to control who gets hit. And since Deeth is level 800 Musaka and Casibal are both 600, you can level up to 800, if you really want.

For level-ups, you want all your front-liners to have 999 Strength, pre-equipment. If they have 150 Vitality, you'll hit the maximum health (99,999) relatively quickly. Dyshana maxes out Int at 999, pre-equipment. From there, level up Agility to about 350-360, so you'll go first in battle even against Nil and the gods. Even though the screen will only display 9999 attack and 9999 magic, the game still knows to take the total of everything. Level up Luck after Strength, to give you even better odds of hitting.

For Actives, you want the +999 attack on all the front-liners, and +999 magic for all of Dyshana's Active Slots. Once you've maxed Strength and started on Luck, they'll be hitting hard, and consistently, so you don't need +Accuracy or +Strength. Keep using the Combo Arts I listed and EX Skills as necessary, and you'll have almost no trouble with anyone. Use U-Formation (everyone's EX3), and you'll kill Dark Dyshana and Chaos in just one attack.

This achievement is called "Conqueror of the Planes"

You will get this after defeating Chaos (Level 999) in the boundary plane.

You need to be playing on hard difficulty to get this achievement. This is the last of the postgame bosses, so if you get this achievement you should congradulate yourself on a job well done.