If I were a hero, I'd be Martin Luther (Part 2272)...

 Superhero Anydays

Today, don't know the artist, but we have their version of the Justice Society Of America!

Roughly, clockwise from upper right: (don't know the lady on top, but it looks like Jade), Spectre, Hawkgirl, Green Lantern,  Obsidian (small and by GL's arm), Stargirl, Red Tornado, possibly Hourman II, Wildcat II, Wildcat I, a female (?) Dr. Mid-Nite, Robin, Liberty Belle, Wonder Woman, Huntress, The Flash, Hourman I, Johnny Thunder, Black Canary, Mr. Terrific II, Dr. Mid-Nite I (and his owl Hooty), Dr. Fate, Starman, Power Girl, Johnny Thunder's Thunderbolt.  Hawkman is in the middle with Sandman between his feet.

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And we have three very powerful cosplayers: Captain Marvel, Superman, and Superboy.

POLT