The Flash deals with the Negative Speed Force and then has to solve a murder inside Iron Heights in Flash, Volume 6: Cold Day in Hell.
A boy comes from Japan to Gotham looking for his parents in Batman and the Justice League, Volume 1.
Wonder Woman and Batman get into a long fight on behalf of the Gentleman and then Poison Ivy takes over the entire world except for Batman and Catwoman in Batman, Volume 6: Bride or Burglar.
Ms. Marvel goes full in for hero-on-hero fighting in Civil War: Ms. Marvel, Volume 2.
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