Blue Ultima Weapon?

[Mirage]

My regular attacks always deal 9999 damage when I have 8k and more HP, even against targets with relatively high defence, however, each hit with Omnislash only deals ~9500 damage each hit (regardless of current HP), or a bit less if the enemy has high defence. This is with 255 attack power.

As for his other limits, they deal 9999 damage, but you can get 9999 meteorain with far from 255 attack power, same with many other limits.
And this is why we don't like reachable limits :(.