Supergirl #16

Part of the sprawling "H'el on Earth" crossover, Supergirl #16 from 2013 delivers a charged team-up moment right on its cover — Supergirl and the Flash charge forward side by side, fists raised and expressions fierce, with a dark figure tumbling in the background hinting at the conflict ahead. Mahmud Asrar's cover art crackles with kinetic energy, the Flash's lightning trail and Supergirl's determined grimace making it clear these two heavy-hitters are in the thick of something serious. Mike Johnson and Asrar were crafting one of the New 52's more dynamic Supergirl runs, and this guest-starring Flash issue looks like a high-velocity highlight.