And by memorable, I mean memorable for a reason other than longevity. Sure, Mario and Link are recognizable to almost anybody, but why? Mario has no story at all, and Link has simply become a "role" that people take on, instead of an actual character himself. Remember, it's memorable, not recognizable.
Few characters in videogames are given the chance to have any kind of real history to them. Big Boss first showed up as a commanding officer and main badguy in the NES Metal Gear games. Years later, on the PlayStation, he was a thing of legend and myth; on the PlayStation 2, all was revealed, and players discovered his story first hand. By the PS3, Big Boss finally had the pivotal moment between himself and Solid Snake, and cemented himself as a legendary character in video gaming.
Some of the best character development you'll find in a game. Ocelot was a revelation in MGS3, the game that locked him in as a truly unforgettable character. After that game, it was hard not to be a fan.
Anybody who played Portal was blindsided by the humor and story GLaDOS brought to what initially appeared to just be a fun and unique puzzle game. GLaDOS already has a bigger fanbase than most characters, after only one game.
A lot of games let you decide what actions to take, but very few manage to do this but also give the main star real character. Despite making all the choices for Shepard, his design and voice acting all feel as if every choice was the right one. He still feels like his own character, not just an extension of the player like most choose-your-destiny games.
Agent 47 is without a doubt an iconic character from a design standpoint alone. Add in his backstory, being a genetically engineered clone of the best assassins in the world, and he becomes even richer.
This is more of a testament to BioShock's impressive story telling. The lore of Andrew Ryan leading to his dramatic reveal was excellent, and the big twist truly made Andrew Ryan a memorable name and figure.
Psycho Mantis is one boss fight players will never forget. Metal Gear has always loved to break the fourth wall, but Mantis destroyed it completely, and just the mere hint of him in MGS4 had people excited.
Thanks largely to the voice of Mike Patton, the eponymous character of The Darkness has left a lasting impression.
Grand Theft Auto has been, so far, hit or miss with the protagonists. The only two truly memorable characters are Niko, and Vice Cities Tommy Verceti. Sure, Tommy had the talents of Ray Liotta and the Scarface vibe to boot, but who can forget Niko and his cousin? While Verceti paid homage, Niko is completely unique in the world of main characters.
The only character to appear in all Fallout games, Harold originally started out as a vault dweller who began sprouting branches from his body after being exposed to radiation. By Fallout 3, he was almost entirely a tree, rooted to the ground and worshiped by those around him.
Ryo may not be the most original design, or have the most creative story angle, but those who fell in love with the Shenmue games will always remember him and his ridiculous phrases.
Part of the Elder Scrolls lore for years, Sheogorath's appearance as the Lord of Madness in the Oblivion expansion Shivering Isles is one for the ages. This guy is crazy.
While still new to the scene, Drake has almost singlehandedly brought back the adventure game that Lara Croft brought back. He has all the classic quirks that you'd find in characters like Indiana Jones, but remains his own character and helped remind us how cinematic--and fun--games can get.
