Characters created by Mike Sekowsky

Superwoman is the name of several fictional characters from DC Comics. Most of them are, like Supergirl, women with powers similar to those of Superman, such as flight, invulnerability, and enhanced strength.

Queen Bee is the name of four different DC Comics supervillains.

The Crime Syndicate are teams of supervillains from one of DC Comics' parallel universes where they are the evil counterparts of the Justice League. The original team was specifically known as the Crime Syndicate of America and is sometimes abbreviated as CSA. This first superpowered Crime Syndicate team appeared in Justice League of America #29 in August 1964. The primary successive incarnation, known as the Crime Syndicate of Amerika (with the variant spelling of America), first appeared in the 2000 JLA: Earth 2 graphic novel.

B'wana Beast is a fictional character, a superhero, in the DC Universe, who can communicate with and merge animals. He first appeared in Showcase #66 (January 1967) and was created by Bob Haney and Mike Sekowsky.

Despero is a fictional supervillain that appears in comic books published by DC Comics. The character first appears in Justice League of America #1 (October 1960) and was created by Gardner Fox and Mike Sekowsky.

Showcase is a comic anthology series published by DC Comics. The general theme of the series was to feature new and minor characters as a way to gauge reader interest in them, without the difficulty and risk of featuring untested characters in their own ongoing titles. Showcase is regarded as the most successful of such tryout series, having been published continuously for more than 14 years, launching numerous popular titles, and maintaining a considerable readership of its own. The series ran from March–April 1956 to September 1970, suspending publication with issue #93, and then was revived for eleven issues from August 1977 to September 1978.

Sardath is a science fiction character appearing in American comic books published by DC Comics. Created by editor Gardner Fox and Mike Sekowsky, he first appeared in Showcase #17 (November 1958).

Superwoman is the name of several fictional characters from DC Comics. Most of them are, like Supergirl, women with powers similar to those of Superman, such as flight, invulnerability, and enhanced strength.

Robin of Earth-Two is an alternate version of the superhero Robin, who appears in American comic books published by DC Comics. The character was introduced after DC Comics created Earth-Two, a parallel world that was retroactively established as the home of characters which had been published in the Golden Age of comic books. This allowed creators to publish comic books taking place in current continuity while being able to disregard Golden Age stories featuring Robin, solving an incongruity, as Robin had been published as a single ongoing incarnation since inception. Unlike his main counterpart, Robin is the only alter ego of Dick Grayson, who uses the title into adulthood, rather than taking on later codenames such as Nightwing or Batman. In addition, the name "Robin" is not taken on by later characters.

I Ching (often spelled I-Ching) is a fictional, blind martial artist published by DC Comics. He first appeared in Wonder Woman #179 (November 1968), and was created by Denny O'Neil and Mike Sekowsky. The character was created to further the editorial plans to reboot Wonder Woman's premise and characters.