Super Miracle Cube

I mean, adding a line and changing rank is completely different thing.

I would not expect 60% claw for attack scrolls selling at the same price as 60% pet eq for speed scrolls.

...

I'm not talking about what the cubes do. I'm talking about the rates of them changing something from Rare to Epic or from 2 line to 3 line.
Premium Cubes are said to have a 25% chance of changing something from 2 line to 3 line.