Video Games With Mods That Improve Their Overall Performance and Quality, If Not Eclipse the Original Version Completely.
- Deus Ex > GMDX (Give Me Deus Ex) and The Nameless Mod fangame
- Thief: Deadly Shadows > Sneaky Upgrade
- FreeSpace 2 > FSPort+Silent Threat: Reborn, Derelict, and Blue Planet, among many others (particularly The Babylon Project, Shrouding the Light+StL: Origins, Sync, Transcend, Vassago’s Dirge, the Just Another Day series, and so on)
- Star Wars: X-Wing Alliance > Upgrade (can even apply with TIE Fighter > Total Conversion Mod)
- Pathways Into Darkness and The Marathon Trilogy (1, 2: Durandal, and Infinity) > Aleph One
- Battlefield 2 > Project Reality: BF2 and Forgotten Hope 2
- Battlefield 1942 > Forgotten Hope
- Call of Duty 2 > Spanish Civil War Mod
- Commandos 2: Men of Courage > Commandos: Destination Berlin
- Star Wars: Empire at War+Forces of Corruption > Thrawn’s Revenge, Fall of the Republic, and Awakening of the Rebellion
- XCOM: Enemy Unknown and 2 > The Long War
- Command and Conquer: Red Alert 2+Yuri’s Revenge > Mental Omega 3.3.5
- Vampire: The Masquerade - Bloodlines > Basic and Plus Unofficial Patches
- Fallout 1 and 2 > Fixt mod and The Restoration Project respectively (and this is just ignoring the mods for 3, New Vegas, and 4, especially the Someguy series for NV)
- Elite > Oolite
