First Appearance: House of Secrets #61, 1963

First Meeting with Booster Gold: Justice League America Annual #6, 1992

Encounters with Booster Gold: 7

Before the SEPCTRE was the personification of the Spirit of Vengeance, Eclipso held that title. Reawakened centuries later by Bruce Gordon (see SHADOW FIGHTERS), Eclipso returned to regain the power that had once been his to wield.

Booster Gold first encountered Eclipso when he dominated JUSTICE LEAGUE member Maxima. Later Booster would join the other HEROES UNITED AGAINST ECLIPSO in an ill-fated assault on Eclipso's moon stronghold.

First Appearance: Adventure Comics #352, 1967

First Meeting with Booster Gold: Booster Gold, Vol. 2, #32, 2010

Encounters with Booster Gold: 1

Emerald Emerald is a long-time foe of the Legion of Super-Heroes. Often allied with the Fatal Five, Emerald Empress utilizes the powerful Emerald Eye of Ekron in her crusade against order.

Booster Gold struggled to defend a busload of ill-fated, including Earthling Jennaux Riel, from Emerald Empress' bloodlust during their first encounter on the planet Daxam during the Great Darkness War.

First Appearance: Our Army At War #151, 1965

First Meeting with Booster Gold: Booster Gold, Vol. 2, #16, 2009

Encounters with Booster Gold: 1

The pride of the German Flying Corps of the first Great War, Hans von Hammer would become the legendary Enemy Ace, greatest flying ace in military history.

Booster Gold was captured by Enemy Ace during an unintended visit to the battlefields of World War I, at which time Booster was impressed by von Hammer's honor and virtue despite his fearsome reputation.

First Appearance: Elongated Man, Vol. 1, #1, 1992

First Meeting with Booster Gold: Justice League Europe #50, 1993

Membership: Brautwurst, Gyro, Il Calimari, LEscargot, Lutefisk, Toad-in-the-Hole

Eurocrime is a criminal organization composed of members from throughout Europe, each with a food motif.

Booster Gold and the JUSTICE LEAGUE confronted Eurocrime when the criminals were employed by SONAR.

First Appearance: Justice League America, Vol. 1, #80, 1993

First Meeting with Booster Gold: Justice League America #84, 1994

Encounters with Booster Gold: 2

Ewald is the brother of JUSTICE LEAGUE member Ice (see FIRE & ICE) and the heir to the throne of their ice kingdom.

When Ewald, corrupted by the influence of the OVERMASTER, overthrew his father and imprisoned Ice, the Booster Gold and the Justice League responded to the plea of Ice's mother, Queen Olaf, and rushed to Ice's aid.

First Appearance: Extreme Justice, Vol. 1, #15, 1996

First Meeting with Booster Gold: Extreme Justice #15, 1996

Encounters with Booster Gold: 2

The Ruling Council of Exor, made up entirely of sets of twins native to the planet Exor, were willing to sacrifice their citizens to slavery in order to obtain powerful technology from the Slavelord.

Booster Gold and EXTREME JUSTICE sided with rogue Exorians Zan and Jayna (see WONDER TWINS) against the Ruling Council in order to wrest control of the powerful Flesh Driver armor away from the corrupt Ruling Council.

First Appearance: Zero Hour #4, 1994

First Meeting with Booster Gold: Booster Gold, Vol. 2, #0, 2008

Encounters with Booster Gold: 1

Determined to manipulate history to his own fiendish desires, Hank Hall (formerly known as Hawk, member of the TEEN TITANS) abandoned his role as MONARCH to assume the alter ego of the villainous Extant.

Extant's meddling with history initiated the crisis known as Zero Hour. As one of the HEROES OF ZERO HOUR, Booster Gold was affected by Extant's plans when he battled a displaced city from his native 25th century. Booster would later encounter Extant and another Zero Hour villain, Parallax, during a trip through the timestream with RIP HUNTER.

First Appearance: Justice League Europe #15, 1990

First Meeting with Booster Gold: Justice League America #89, 1994

Membership: Doctor Diehard, Dreamslayer, Gorgon, Lord Havok, Tracer

The Extremists were the preeminent team of super villains of the alternate universe world of Angor. Following the destruction of their world, the ethereal Dreamslayer traveled to Earth and continued his rampage with robotic duplicates of his deceased teammates. The robots were constructed by the idiosyncratic Mitch Wacky, along with the ASSEMBLERS, one of the few survivors of the destroyed world of Angor.

While the European branch of the JUSTICE LEAGUE often found themselves at odds with the Extremists and anecdotal evidence indicates that Booster Gold may have battled the Extremists in the past, Booster Gold did not directly combat Dreamslayer until he commanded the NEW EXTREMISTS.