What was Weissman/Ouroboros's final goal again though? He wanted to get the power, and then use it to...?
I think there actually was a split right at the very end.
Weissmann wanted to use the power of the Aureole to forcibly evolve humanity to a higher, more "rational" state. However, after he loses to the party and runs away, right before he encounters Kevin he starts talking to himself about how he thinks the Grandmaster was "testing" him too (rather than just him "testing" the SC party) and that him losing was actually foreseen by the Grandmaster and that he intended to have words with them about it when he returned. Of course he gets shot by Kevin a minute later but given Campanella pops in to grab the Aureole (which was still in his staff) and in 3rd claims turning it over to the Grandmaster is his most important duty in Star Door 14's meeting I think the clear implication is that Ouroboros's goal was to get the Aureole (for still unclear reasons) but that Weissmann was under the mistaken impression that he was cleared to use it to try and remake humanity into his ideal.
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xp1337: Don't you wish there was a spell-checker that told you when you a word out?