Though it hasn't released many original games in the last decade, Valve's history of industry-changing titles has made them a powerful force in gaming. Valve has been mostly known for operating Steam (as well as CS:GO and DOTA 2), but their past titles are what made the company what it is today.
One thing that set Valve games apart from other titles of their time was their completely unique characters. Before Portal, the use of a snarky and oftentimes rude narrator was completely new, and the memorable characters of the Left 4 Dead series made battling the hordes less horrific. For all of their iconic characters, though, only some have stayed in the gaming zeitgeist even in 2021.
10 Phoenix Terrorist - Counter-Strike: Source / CS:GO
Counter-Strike: Source (CSS) was an absolutely massive game in the early PC days of the 2000s. Just like in CS:GO, there's a team of Terrorists and a team of Counter-Terrorists with a handful of player models to choose from upon spawn for each side.
Most CSS players will recognize the Phoenix Terrorist skin instantly; it was the most popular skin for the Terrorist side and something of an iconic character for CSS in general, even without any kind of personality or story attached to it.
9 Cave Johnson - Portal 2
One doesn't have to stray too far into the gamer side of the internet to find Cave Johnson quotes still posted everywhere to this day. He's voiced by none other than J.K. Simmons, the actor behind J. Jonah Jameson in the Spider-Man movies, and his narration throughout Portal 2 is, in a word, memorable.
Portal 2 fans won't soon forget his rant on what to do when life gives you lemons, nor will they forget his haphazard approach to scientific safety.
8 G-Man - Half-Life / Half-Life 2
The enigmatic G-Man from the Half-Life series is the first character players meet in Half-Life 2 in the introductory cutscene, and his role in the game is still something of a mystery for many. His deeply disturbing face, along with his businessman appearance and briefcase, make for one unsettling NPC.
PC gamers who started their Source Engine journey in Garry's Mod find it hard to take the character seriously anymore, but nonetheless, he's one spooky dude with a strange manner of speech.
7 Ellis - Left 4 Dead 2
Every character from the Left 4 Dead series is memorable in their own way. Coach is loud and large, Francis always has an attitude, Louis goes hog-wild for some pills, and Zoey and Bill have some great interactions. But out of all eight survivors across both games, Ellis stands out.
He's bombastic, he has no filter, he always seems to misunderstand what's going on, and his voice lines consequently are the funniest in the game thanks to his absurd reactions to most situations.
6 Chell - Portal / Portal 2
While the player never really sees Chell in either Portal or Portal 2 without the use of portals, she is nonetheless one of Valve's most iconic and instantly recognizable characters. As the protagonist (and player character) of both games, she is at the center of it all.
Chell's model depicts her as a Latina or multiracial woman wearing an orange Aperture Science jumpsuit, sometimes tied around her waist. She doesn't say anything during the game, too, which prompts GLaDOS to call her a "dangerous, mute lunatic" – an apt description, all things considered.
5 The Boomer - Left 4 Dead
Of all the special zombies in the Left 4 Dead series, the Boomer is the most iconic. While the Witch might be more terrifying, or the Spitter more deadly, the engorged, explosive mass of a Boomer makes them stand above the rest of the horde.
Much of Left 4 Dead was inspired by zombie classics like Dawn of the Dead and 28 Days Later, but the Boomer is one grotesque zombie archetype that Valve can call their own.
4 Gordon Freeman - Half-Life / Half-Life 2
The Half-Life series has always been at the forefront of gaming technology-wise, and it's one of the only series where the protagonist is an accomplished Ph.D. scientist. Despite never being seen in either Half-Life or Half-Life 2, Gordon Freeman is instantly recognizable thanks to the games' box art (as well as countless memes).
While he's not a particularly interesting character on his own, Gordon Freeman is central to the plot in both games. There might not ever be a Half-Life 3, but if there is, Gordon Freeman will certainly be brought back, crowbar in hand.
3 The Heavy - Team Fortress 2
There are 9 playable classes in Team Fortress 2, each with their own complete personalities, quirks, and of course playstyle differences. They're all iconic and hilarious in their own way, but the Heavy is most commonly used to represent the game across the board.
Poker Night at the Inventory features the Heavy as a player, for example. His voice lines and character model have probably been used in more Garrys Mod videos than one can count, too.
2 Alyx Vance - Half-Life 2
Alyx Vance is one of the main protagonists throughout Half-Life 2, and even received her own prequel game in 2020 for VR titled Half-Life: Alyx. She's central to the player finding their way throughout Half-Life 2 and its DLCs, and she's nothing if not encouraging and earnest.
She's a serious force to be reckoned with in combat, too – and Alyx isn't just the daughter of a scientist, she's a scientist in her own right too. She's a fantastic companion and the progression of her story through both episodes is often more engaging and heart-wrenching than Gordon Freeman's.
1 GLaDOS - Portal / Portal 2
When one considers the most iconic Valve characters, there's nobody who can top GLaDOS. Before Portal, the idea of using a sarcastic and often downright antagonistic narrator was nearly unheard of, but now it's nearly impossible to find a sci-fi puzzle game without one.
GLaDOS has some of the most iconic lines in gaming history and is an enemy completely unique to the Portal series. The songs GLaDOS sings at the end of each game are fantastic, if not a bit overplayed, and the character's influence on modern games and snarky narrators cannot be understated.