Infinity, Inc.

Infinity, Inc. is a superhero team developed by American comic book writer Roy Thomas in the early 1980s, consisting of members that are children or proteges of various Justice Society of America members. The team was brought together by the JSA's youngest member, the Star-Spangled Kid, for the purpose of showing the worth of the younger generation of superheroes, who felt put-down by their parents and mentors. They existed on Earth-2, a Parallel Universe which featured the original, now older, versions of many of The DCU's heroes. The original lineup was:

Star-Spangled Kid, time-displaced Golden Age Kid Hero. Originally just a Badass Normal (with a lot of money), later owned a "cosmic coverter belt" that gave him Green Lantern-like powers. Later changed his name (and costume) to Skyman. Eventually killed in battle; his identity (of Star Spangled Kid) was later picked up by a teenage girl.
Brainwave, Jr., son of JSA supervillain Brainwave. Had Psychic Powers.
The Fury, daughter of Wonder Woman and her long-time Love Interest, Steve trevor. Same powers as her mother (except without a magic lasso.)
The Huntress, daughter of Batman and Catwoman. Left after their first adventure.
Jade and Obsidian, children of Green Lantern (Alan Scott) and one of his old enemies, The Thorn. Jade had the same powers as her father, while her brother Obsidian could turn into a Living Shadow.
Northwind, godson of the original Hawkman and Hawkgirl. Son of an African American researcher and a member of a hidden race of Bird People.
Nuklon, godson of the original Atom and son of the (reluctant) atomic villain, Cyclotron. Can grow to giant size.
Power Girl, cousin/adopted daughter of the original Superman. Also left after their first adventure.
'Silver Scarab', biological son of Hawkman and Hawkgirl; wore a magical armor.

They were later joined by the new Hourman, son of the original; new versions of the Badass Normal heroes Doctor Midnight and Wildcat, who were merely trained by their predecessors; and redeemed villains Solomon Grundy and Mister Bones.

Infinity, Inc. was hit hard by Earth-2's merging with four other Earths during Crisis on Infinite Earths. With the team rewritten to have originated on the post-Crisis Earth, they were left without much of their backstory, including Batman, Superman, and Wonder Woman. The book floundered for a few more years before cancellation.

As adults, most of the 'Infinitors' have since gone on to join the JSA or the JLA as full members.

A new Infinity, Inc. for the twenty-first century debuted in the miniseries 52. They were entirely new characters with no connection to the originals. Steel's niece Natasha Irons was a member for a short time.

Tropes used in Infinity, Inc. include:

Bad Powers, Bad People
The Big Guy: Nuklon.
Central Theme: Age vs. Youth.
Dangerous Deserter
Eighties Hair: Nuklon and his crazy-ass mohawk, which might have looked cool a few decades ago.
Fan of the Past
Gender Bender
Half-Human Hybrid: Northwind, who became more avian in appearance in later years.
Heel Face Turn: Mister Bones.
Legacy Character
Mayfly-December Romance
Redeeming Replacement: Brainwave.
Spin Offspring
What Could Have Been: There was initially going to be a character called Harlequin (after the original Green Lantern villain-turned-heroine) who was to be DC's first openly gay character, but he was scrapped because there were already two GL-related characters and the roster was getting crowded. The new Harlequin character ended up as a villain who was part of the Wizard's Injustice Unlimited team. The original Harlequin later married Green Lantern. (Neither should be confused with Harley Quinn.)

The new Infinity, Inc. provides examples of:

Central Theme: Former young Jerkasses learning how to be responsible adult heroes.
Dirty Coward: They run away from the fight when Black Adam goes berserk.
- Then again, he was an invincible Hero-Killer.
Dropped a Bridge on Him: Most of their number have met brutal, pointless deaths. In fact that seems to have been their purpose all along, since they were just a part of Steel's subplot in 52.
In Name Only: In-universe--the members of the team have no personal connection with the people whose names they have assumed. The copyrights for the original identities were purchased by Lex Luthor and he distributed them to the new team. (This might have been a subtle hint that the team itself was created just so DC would not lose the trademark to its name.)
Miles Gloriosus
Mind Screw: The series starring Infinity, Inc. after 52 was... weird, to say the least.
Transsexualism: Fury/Amazing Woman. Possibly DC's first transgendered superhero.
- Technically, Coagula of Doom Patrol came first, even if she appeared while the books was under the Vertigo header.
What Kind of Lame Power Is Heart, Anyway?