How this battle will work, is you must kill both of the Generals on the same turn or it's an instant game over. That's why balanced teams are so important. If you have two physical attackers (Kaim and Seth) and two magic casters (Sarah and Jansen) to make up each team your damage should be pretty balanced. Keep an eye on the HP of each general shown in the upper-hand corner of the screen Things to make note of, are that the monsters will heal for about 530HP each turn, unless you have Sed use Adjust Output, which will stop this healing process once. This can be useful if one of your attackers scores a critical hit, or something to that effect; you would want to make up for it by not letting the other general heal. Balance: Balance is the key to this battle. Aside from Forceus, neither of the Generals attacks are all that bad, and the fight shouldn't be too difficult providing your not under-leveled. If you are, you can always level right in the area. 45 or so should do it. During the fight, have Sed alternate between adjusting the output, to keep things balanced, while not allowing either General to heal as much as they usually do.
Alternative strategy: just use Divide with Kaim and Seth.