Title: SECRET WARS II#2 by Jim Shooter (writer) and ___________
Synopsis: After the Hate-Monger's (and Pyscho-Man's) plans start to fall apart, Scourge, hidden in an alley, guns down the Hate-Monger, revealing him to be an android (I think; the readers might have known earlier and I'm not 100% sure the public found out, but I think they did at this point).
Is it key to the Scourge storyline? No
Does it tie in to the main story? Only to the extent that Secret Wars II covers events from Fantastic Four#280. Since Psycho-Man begins using the android there, Scourge's hit actually ties more into that story.
Comments: This is the only Scourge victim to be killed in his first outing, as well as the only one to be an artificial lifeform.
Scourge's disguise, if any, is not actually seen here.