Yay!! Someone's playing FFIV!
I'll be glad to help.
Okay, this strategy requires that Rydia knows Bio/Virus, and Rosa knows Haste and Berserk.
Rosa should Haste and Berserk Cecil and Kain, and if you have any Bacchus' Wines or Hermes' Shoes (it depends on what version you have.), have them use those on themselves first (Cecil and Kain.) Do not Berserk Edge, though Hasting him would help. He should throw stars and whatever else uneccessary weapons you don't use anymore at the wall. And finally, Rydia should cast Bio (Called 'Virus' in the NA SNES version.) to poison the wall. (This helps tremendously.) You'd be surprised how much damage hasted-berserked fighters do
After Rydia uses Bio, she should keep on summoning Titan, or if you got it yet, Leviathan. The reason you don't berserk Edge is so he can use items if anyone dies/ runs out of MP/ etc. After Rosa enchants the fighters, have her heal when neccessary.
Hope that helps! Evil Wall can be a pain, especially on HardType. (What version are you playing anyway?
)
Edit: Although it's harsh, if you don't have those spells I mentioned, go outside and train, or kill off any Trap Doors you didn't kill. (Since every door there is one anyway
) These spells are very useful. (For that point in the game.)