thanks to Brian Cronin ans the readers of the CBR for their votes, let's begin.
100. Superboy Prime vs. Teen Titans (Infinite Crisis)
In Infinite Crisis #4 by Geoff Johns and Phil Jimenez, the Superboy from Earth-Prime (who has been trapped in a sort of multiverse limbo since the events of Crisis on Infinite Earths) travels to the home of Jonathan and Martha Kent to try to make some sense of the modern DC world (and Alex Luthor’s plans for it). When there, he confronts Conner Kent, the Superboy of this world. After an awkward interaction, Superboy Prime (being a bit of a chump) decides to take out his aggression on Conner.
Conner is pretty out-classed, but help is on its way, in the form of pretty much every Teen Titan (or Titan-related character, period)!!!
They hope to settle things peacefully, but, well, things go a bit awry.
Prime proceeds to take apart the Titans pretty easily (and viciously, killing another Titan and tearing the arm of one), and the day is only saved by the combined force of the Flashes, who take Prime into the Speed Force basically.