I've beaten it more times than I can remember. Each time I've tried a different approach.

I've tried the speed run to try get Excalibur 2 but I've failed at both attempts of trying...

I've also tried getting really high levels near the beginning by getting characters to level 25's in Evil Forest. Dagger was able to use Shiva against the monsters in the Ice Cavern. I also got to level 60 at Gizamaluke's Grotto by fighting Garudas and then when I got high enough, I fought Grand Dragons. You have to be seriously lucky to beat one but wow, the experience is amazing for the beginning! I got to level 99 at the third disc fighting in the same place, haha! xD

I also had a casual game where I took it slow and steady and I've tried different character parties as well...