Sturm can't progress its catalyst if paired with Drang (Baroque). I'm not sure if this is intended, but since the Baroque version of Drang synergizes with Sturm in the same way the original version does, it seems like it would.
Skyburner's Oath needs Cabal kills to progress, but Cabal on the Derelict Leviathan don't count towards its progression.
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Cabals on the Leviathan have never counted for Skyburner's Oath catalyst, even on the old Leviathan. About Sturm, have no clue really, but Banshee should be still selling the original Drang.