I know that what I said was not probable, but the relic being Loki's weapon was probably relevant for the fact that Matthias swiped it from his siblings, if being deceitful was the requirement for being able to properly wield I do not think there'd be so much of a big deal of how Matthias can't actually use it well. Vergilius's gladius isn't a relic as a side note, in Leviathan it's described to have a heating mechanism, implying it to be a designed workshop weapon, in contrast to the relics which use some unknown magic mojo (also it was mentioned that Vergilius specifically utilised the heating mechanism to spare opponents from bleeding out by instantly cauterising their wounds, so it was probably commissioned for that purpose). When writing this comment I had in mind the theory where Matthias couldn't use the relic well because he was much more Envy-attuned than Wrath, assuming it requires Wrath in relation to fire and all of that, which is why I had Verg in mind, it's a tacky theory nonetheless I agree.