Free alternatives to classic games

[MrFlibble]

Just as the title suggests, this is an attempt to list free games that very closely follow a well-known product or franchise and can thus serve as an alternative to that particular game. These are mostly non-commercial projects, but shareware and liberated (formerly commercial) games are also included, and marked accordingly (by an S or an L).

What I have not included on the list are multiplayer-only games, browser-based games, and all kinds of free-to-play and "freemium" online products. I have also tried not to include projects that make use of original assets like graphics and sounds (unless authorized by original copyright holders, as is the case of T2002), so games like Mortal Kombat Project, Gods Deluxe or Return of the Triad are not on the list. Another thing out of the scope of this list are engine recreations that require original game assets to work.

Any further suggestions as to what games qualify as free alternatives are more then welcome

Age of Empires

• 0 A.D.

Anno series

• Unknown Horizons

Battle Isle 2200

• Advanced Strategic Command
• Crimson Fields

BoulderDash

• Rocks'n'Diamonds

Castlevania series

• Return of Egypt

Chaos

• Chaos Reborn

Command & Conquer

• Dark Konflict

Command & Conquer: Renegade

• Red Alert: A Path Beyond

Crimsonland

• Violetland

Dark Colony

• Dark Hive

Diablo

• Fire & Dragons
• Flare
• Gates of Destiny
• ShadowFlare S
• Summoning Wars

Doom

• Chex Quest L
• Freedoom
• Harmony

Doom II

• HacX L

Duke Nukem

• Bio Menace L
• Space Chase S

Dune II

• Arrakis

Earth 2150

• Warzone 2100 L

Earthworm Jim

• Kapitan Binarny

Elite

• Oolite

Exile series

• Realmz L

Grand Theft Auto series

• Crimelife
• Crimelife 2
• Crimelife III

Guitar Hero

• Frets on Fire

Gun

• Guns and Spurs

Half-Life: Counterstrike

• AssaultCube

Heretic

• Blasphemer

Heroes of Might and Magic series

• Knights of War

Jill of the Jungle

• Xargon L

KKnD

• Bos Wars

Legends of Valour

• The Elder Scrolls: Arena L
• The Elder Scrolls II: Daggerfall L

Lemmings

• Pingus

Lost Vikings

• Lost Snowmen

Master of Magic

• Continents
• Leylines

Master of Orion

• FreeOrion

Microsoft Flight Simulator

• FlightGear

Might and Magic series

• Ancients I: The Deathwatch S
• The Infernal Tome S
• Yendorian Tales Book I: Chapter 2 S
• Yendorian Tales: The Tyrants of Thaine S

The Need For Speed

• Dolphinity Racer

Quake III: Arena

• Alien Arena
• Nexuiz Classic
• OpenArena
• Warsow
• Xonotic

Scorched Earth

• Atomic Tanks

Secret Agent

• Special Agent

The Settlers II: Veni, Vidi, Vici

• Widelands

Sid Meier's Civilization II

• C-evo
• Freeciv

Sid Meier's Colonization

• FreeCol

SimCity

• City of Rauma
• Kylavanem

Sonic the Hedgehog

• Skunny: Special Edition S

Space Hulk

• Alien Assault

StarCraft

• Priority: Survive

Street Fighter II

• Sango Fighter L
• Super Fighter L

Super Mario Bros.

• Commander Keen: Invasion of the Vorticons S
• Secret Maryo Chronicles
• Super Angelo S
• SuperTux

Super Mario Kart

• Skunny Kart S
• Super Worms S
• SuperTuxKart
• Wacky Wheels S

Total Annihilation

• Spring

Transport Tycoon Deluxe

• OpenTTD

Turrican series

• Hurrican
• T2002

Ultima I-V

• Excelsior Phase One: Lysandia S
• The Fantasy Worlds of Tamrak S
• Hera: Sword of Rhin S
• The Kingdom of Syree
• The Kingdom of Syree II: Black Magic S
• The Kingdom of Syree III: The Depths of Hell S
• Nerakian Adventure S
• The Rescue of Lorri in Lorrinitron S
• Silmar S
• Sword Quest 1 S
• Untima IX: Descension
• The Walls of Bratock S
• Zorak: The Mountain of Terror

Ultima VI

• Flame Storm: The Bratockian Saga part II S
• The Great Ultizurkian Underland S
• Joyous Rebel L
• Madman
• Ultizurk III: The Guildmaster's Quest S
• Wraith S
• Yendorian Tales Book I S

Ultima VII

• Excelsior Phase Two: Errondor S

Unreal series

• Cube
• Cube 2: Sauerbraten

Warcraft II: Tides of Darkness

• Dark Oberon

Warcraft III: Reign of Chaos

• Glest

Warsong

• The Battle for Wesnoth

Warlords

• Hostile Takeover S
  Legendary Legions

Warlords II

• FreeLords
• LordsAWar!
• The Wargame Project

Wolfenstein 3D

• Ken's Labyrinth L

Worms

• Hedgewars
• WarMUX

X-COM: Enemy Unknown

• UFO: Alien Invasion

[MrFlibble]

Another World/Flashback

• onEscapee L [download]

Empire Deluxe

• Battles of Destiny L

Master of Orion

• Star Lords L [download]

Robot Odyssey

• DroidQuest
• Gate

Scorched Earth

• Scorched3D

Sonic the Hedgehog

• Skunny: Special Edition S

Super Mario Bros.

• Giana Worlds [download]
• Giant Sisters

Wing Commander series

• RiftSpace L
• Star Wraith 2 L
• Star Wraith: Shadows of Orion L
• Star Wraith IV L
• Vega Strike

[nickherc]

Wow, thank you for this! I'm very intrigued especially by AOE spin off, or how should I call it. Has anyone tried any on the list? Any thoughts?