A-Train

Inspired game: FreeTrain

Abuse

Inspired games: Abuse, Abuse 1996, fRaBs

Ace Combat: Assault Horizon

Inspired game: Open Horizon

Ace of Spades

Inspired games: BetterSpades, Iceball, OpenSpades

Achtung, die Kurve!

Inspired games: Achtung, die Kurve!, Netacka, Zatacka, Zatacka X

Advance Wars

Inspired game: Tanks of Freedom

Age of Empires

Inspired games: 0 A.D., openage

Age of Empires II

Inspired games: freeaoe, openage

Age of Pirates 2: City of Abandoned Ships

Inspired game: Storm Engine

Akalabeth: World of Doom

Inspired game: Aklabeth

Albion

Inspired games: SR, UAlbion

Allegiance

Inspired game: Free Allegiance

Alone in the Dark series

Inspired game: Free in the Dark (engine)

Ambermoon

Inspired game: Ambermoon.net

American Civil War

Inspired game: Greenius' Civil War

Angband

Inspired game: ZAngband

Angry Birds

Inspired game: Apple Flinger

Anno (series)

Inspired game: Unknown Horizons

Anno 1404

Inspired game: Goblin Camp

Another World 2: Heart of the Alien

Inspired game: Heart of the Alien

Aquastax

Inspired game: aquastax

Archon: The Light and the Dark

Inspired game: XArchon

Ares

Inspired games: Antares, XSera

arithmetic

Inspired game: Garith

Arkanoid

Inspired games: Ball And Wall, PyBreak360

ARMA 2

Inspired game: Uebergame

ARMA 3

Inspired game: Uebergame

ARMA: Armed Assault

Inspired game: Uebergame

Armor Alley

Inspired game: Armor Alley

Artemis: Spaceship Bridge Simulator

Inspired games: EmptyEpsilon, Space Nerds In Space

Artillery Duel

Inspired game: Artillery Duel Reloaded

Arx Fatalis

Inspired game: Arx Libertatis

Asteroids

Inspired games: Maelstrom, Sine, StarMines: The Next Generation, Vectoroids

AstroMenace

Inspired game: AstroMenace

Astrosmash

Inspired game: Cosmosmash

Asylum

Inspired game: SDL Asylum

Atomic Bomberman

Inspired games: BomberClone, Bombman

Atomix

Inspired games: Atomiks, Atomix, KAtomic, LMarbles, WAtomic

Awesomenauts

Inspired game: BlakedAwesomenaughts