Isterio said:
Memento Mori from Mard Geer was killing everything in a huge vincinity and could only be countered via plot device, aka Gray sacrificing his arm to the curse or something, because tbh the ability is a plot device itself.
In video games a la final fantasy those instakill abilitities (which Hiro is mimicking) have low hit chances or do not work against bosses making them somewhat niche in their usage and therefore balanced so that they don´t break the game.Even back in Rave there was a character that used such an abilitiy and they countered with a plot device too, as instakill attacks are unblockable, through regular means and do not care whatever attack you send out against them, which Hiro always makes clear before it gets used.
For Hades there is the mention of Grimoire Law and the fact that he was essentially immortal because of his plot device Lacryma. Again he was just beaten because of a hidden weakness, yet his capabilities were huge and they never went toe to toe with him, because he was regenerating any damage back.
While both Hades and Mard Geer are really strong they really don't compare to the Spriggans.
Hades depended too much on his Demon Heart, while the Spriggans are simply strong by nature(at least until now)
Mard Geers' "Memento Mori" like you said it's a plot device itself but no way it compares to Sand World, the scale of the two are completely different, Memento
Mori scale was a little bit larger than the guild base or something like that, while Sand World enveloped the entire city.
I mean, the Spriggans powers will probably be too overpowered like you said, similar to FF attacks, because if Brandish power can be taken by what we've seen, she really could literally shrink the entire city or shrink everybody in the city and just step on them,
Don't get me wrong, it's not like I think both are weak or something like that, but I'm just surprised to how strong the Spriggans are compared to those 2, hence why they keep being overhyped to be on a complete different level than anything before, and we still have yet to see the rest of them and their actual fights.
Hopefully Hiro will bring some actual logic behind of how to counter the Spriggans and not some BS thing like "the power of will".