Easiest: V or VI, it's just so easy to have broken characters in those games. And even without broken characters, the game isn't hard.

Hardest: III and I attribute it all to the lack of save points. The final stretch of the game has you going through eight floors with a boss at the end, followed by another dungeon with five floors and each floor with a boss that was tougher than the boss you just fought and then there's the Cloud of Darkness. That bitch. She gets four turns. And when you start winning she spams Particle Beam, which does around 1200-1800 damage and at that point Refia had the highest HP at 3200.

Quote Originally Posted by shion View Post
I've only played FF1: DoS version, which is harder?
The one on the original Nintendo is way, waaaaaay harder than DoS and Origins.