Authority for the win. Jenny has swallowed supernovas....handling a mystical brawler won't be any harder. And Rose Tatoo could probably counter-act the Death and Decay stuff from Tan's powers, since she's the embodiment of the Spirit of Life.
And even the magical telepathic overload Tan has done sounds a lot like when The Doctor flooded a guy with every paniful memory throughout human history....except not nearly that powerful.
Tan's a beast, and all respect....but it's really kind of a mis-match.
dunno enough about him. But you'd need a legitimate nigh-Skyfather teamkiller to take out The Authority....Jenny and The Doctor alone might be at or above Skyfather (written correctly).
eh? well Tanaraq is actually skyfather level, an elder god even older than the Earth itself. However, Authority wins. Giving the team prep...overkill. Banishment is a simple answer
So did Cpt. Atom. Both insane PIS....and Jenny wasn't old enough to do anything when Lobo showed up. Written to potential, either one of them should've just been turned into daisies, transported, telepathically turned to jello, smashed, or exploded in the first moments of the fight.
...I'm also not sure that the Lobo stories are canon.
And neither one took on the whole team at the same time...it was more individual battles.