Techniques

[ROLO]

what techniques work best against DF? try to list the most effective in his different modes if they are different that is

[T0m]

There's so much information ripe for the taking on this website, if you are willing to look for it. If you go to the beastiary section for PSO 1,2 and 4, you'll find this guide, among many other things. In it you can read all about Falz's weaknesses and about what works best in practice, for all Dark Falz's phases and for all difficulties.
Under the same beastiary section you could also find Episode 1 Enemy Technique Weaknesses if you want to know about the weaknesses of any of the other enemies from Episode 1.

[ROLO]

That helped plenty thank you!

[Konan]

All the times ive fought Dark Falz, Foie seems to do the most out of the 3 basic spells. if I had to guess Grantz may be his weakness, though it is fairly slow.

[Dongra]

Form one is zonde, form two is barta, form three is foie.

[ROLO]

I always used foie is seemed to work ok but i wanted to make sure that that was the most effective way to kill DF!