Half-Life
Deathmatch Classic ~~~ I forgot if this was Half Life or not.
I consider these the same game, since Deathmatch Classic was pretty much just a competitive Multiplayer for HL1. Also wasn't it free if you had HL1?
Half-Life: Opposing Force
Half-Life: Blue Shift
Were expansions. Opposing Force told the same story from a completely different viewpoint and included new weapons and enemies.
Blue Shift is almost universally regarded as awful.
Half-Life: Source
Half-Life Deathmatch: Source
Nobody can deny that this was a carbon copy, but the whole point was just to put HL1 on the Source engine.
Half-Life 2
Half-Life 2: Deathmatch
New engine, new weapons, new enemies, new characters, frustratingly new story. Also I think Deathmatch was free if you had HL2.
Half-Life 2: Lost Coast
Wasn't that free? I swear I had it before I ever bought a Steam game.
Half-Life 2: Episode One
Half-Life 2: Episode Two
Weren't sold at full price as completely new games.
I may have been wrong about the deathmatch games being free if you had the core game, but the points about EP1 and 2 are still valid. They were designed from the start to just be expansion packs that continued the story after the game had been released and unlike some instances of story-continuing expansion packs (or DLC) they weren't withholding content.
In retrospect, the "same thing = bad" idea seems to mainly apply to multiplayer-oriented games.
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