A person who devotes a large portion of their time towards gaming and gaming variations. A hardcore gamer might often attempt to optimize their playing style, often by the use of gaming gear or mods/addons; this practice is often common for casual gamers, but to some lesser extent.

"A casual gamer is someone who schedules the game around their life, while a hardcore gamer schedules their life around the game." -TotalBiscuit (a.k.a TotalHalibut; The Cynical Brit)
Jim plays World of Warcraft and devotes the majority of his time to his raiding guild, including altering his real life schedule to suit his guild's needs. Hence, he is, to some extent, a hardcore gamer.
by The_Cynical_Gamer March 21, 2011
A Hardcore gamer is a knowledgeable, active and committed individual with a high degree of interest or commitment in playing video games.
Nintendo abandoned the Hardcore gamer when they made the Wii
by Mavronumon July 11, 2016
\A gamer who plays a variety of video games, based only on gameplay, not graphics, story, popularity,etc. They respect the old school, and own multiple consoles, old and new(not a fanboy.) They enjoy playing FPS's, JRPGS, Fighting games, etc. The term also applies to PC gamers.
You are not a hardcore gamer cause you play casual shooters, MLG isn't hardcore, playing ONE game isnt hardcore.
by MaidenPriest420 July 28, 2009
Individuals who put a large amount of time into playing video games; this is what most people refer to as a "true gamer." Contrary to popular belief, hardcore gamers are not people who only play games with extreme violence and gore; hardcore gamers prefer to play games from different genres and franchises. They also feel that gameplay in a video game is the most important aspect of any game; as long as the game is fun (meaning difficulty and graphics don't matter), they will continue playing it. The complete opposite of a hardcore gamer is the "casual gamer."
Gamer 1: Welcome to the gamer's club, what do you play?

Gamer 2: I've been playing Call of Duty ever since it came out; they new one's going to be epic!

Gamer 1: Lol! Your a fucking casual, gtfo! How can you stand that shitty gameplay and those less than impressive graphics; never talk to us hardcore gamers ever again!
by Person12599 June 25, 2013
A videogame enthusiast who does not care what system he/she is playing on, as long as the game in question is both fun (read: controls well, intrigueing and inventive gameplay, ect.) and challenging. A hardcore gamer realises that there is merit to many games on a variety of systems and often owns all of the currently available systems.

One variation on this term would be Insane hardcore gamer: A gamer who owns as many videogames as he/she can possibly get his/her hands on, often never finishing even half of what he/she owns, and also seeking out deals on famous/favourite/rare games just so that they can be added to his/her collection.
Jerry is a hardcore gamer, and owns over 200 games on 9 systems. He is always looking to expand his collection.
by Kokomo_man February 6, 2005
One who spends in excess of more than 4 hours in one sitting. Realises that graphics, story, fun and all the other shit are all equally important. One offsetting the other will affect the game adversely
Many people claim to be hardcore gamers, but they are just posers. as stated above, all of the mentioned above are needed equally in order to make a kickass game.
by chrisguy March 7, 2005
True gamer. Me. Any gamer who has played videogames since they learned sub-basic motor skills, and who go into the past, before they were born, and pla every retro system out there. I agree Hardcore gamers and Casual gamers are mortal enemies. Hardcore gamers, for one, see past the greatest reason why we are mortal enemies. GRAPHICS. Who cares if a game has sub-par gfx for the system its on? If its a great game with great handling, story, action, WHO GIVES 2 SHITS ABOUT GFX? Graphics is only eye candy. Which is how you can discern the true gamers from posers because true gamers can always be found with a full library of NES, Atari, SNES, Genesis, GB (dot matrix screen), Virtual Boy, and any other lesser known systems.
Hardcore gamer: Me 'n my cuz. Hardcore 2 tha bone
Casual (poser): Johan (always thinks he's better than the 'hwhite boi' because he plays only new shit.
by H4rd(0r3 fo' 3v4 November 30, 2004