Instead of doing heroic deeds, like saving a village from being flooded by a dam, they would break the dam open more, so as to destroy the village.
The Super Enemies have no morals. They are evil incarnate.
Silver Age Background
On the parallel-universe of Earth-Three, there were evil counterparts of the Justice League of America, called the Crime Syndicate of America. On this parallel earth, history was "reversed" and Lex Luthor used his vast intelligence for good. The Crime Syndicate eventually discovered the existence of Earth-One and Earth-Two, and set out to challenge the JLA and JSA to a lengthy fight, after which the Syndicate was ultimately defeated, the JLA tricking the Syndicate members into unleashing more power than they could control after they had captured and imprisoned the JSA. Following this defeat, they were imprisoned in an unbreakable bubble generated by Green Lantern's power ring, and placed in a "limbo" dimension between the Earths with multi-lingua signs warning nobody to release them. Over the following years, the Syndicate or one of its members would occasionally escape and attempt to wreak havoc on Earth-One and/or Earth-Two.
Their headquarters is the Hall of Evil.
Total Membership is unknown:
Season 4 (1979):
The Crime Syndicate of America (sometimes abbreviated as CSA) first appeared in Justice League of America, Vol. 1 #29 in August 1964.
Evil Wonder Twins appear in "Universe of Evil" (as does alternate Gleek), but they have no lines, and are only seen in shadow in the opening scene in the darkened Hall of Evil. Also, when evil Superman crosses over to the Super Friends universe, he recognizes Zan and Jayna on sight, more evidence that they have counterparts in his universe.