The thing is, Toad gets very tedious to level up when it reaches level 5+. By the time you get Toad to level 10 or so, it takes forever for it to gain even one level. I'm not even sure if the Toad spell can level up after that if you're just fighting normal enemies. The weapons at least seem to have the stat cap of not leveling up anymore unless you start fighting harder monsters.

Quote Originally Posted by Maxx Power View Post
Yes, eight times Masamunes on all characters would be extremely overpowered. Get yourself 16 Sword Level, 99 Strength, Haste + Berserk +Aura and you could theoretically be looking at 19998 damage per hit under some circumstances. However such damage would be totally unnecessary as to my knowledge nothing in the game has over 60k health anyways.
As far as I know, the Emperor has the highest HP, and he has "only" 10,000 HP (15,000 in the DoS version). Some enemies in the Souls of Rebirth quest have more HP than that, but their HP is still "only" 25,000 HP at max.