"2K6"
Input "Crazy Hops" in the cheat entry screen (located in the "My 2K" menu) to make the ball bounce crazily once it touches the ground. Typing in "Unhittable" will result in pitches that have a ridiculous amount of movement. "Gotcha" gives your players super strong throwing arms. In order to make your defensive players scale the walls and make spectacular plays, type in "Last Chance." Inputting "Dream Team" give you access to the Topps 2K6 all-star team. In order to unlock everything, with the exception of the Topps 2K6 all-star team, use "Derek Jeter" as your cheat code.
"2K7"
Type "Derek Jeter" in the cheat entry screen in order to unlock all bonuses (which can also be unlocked by meeting certain in-game criteria). "Black Sox" will unlock all cheats, and can be toggled on and off in the "Cheats" menu. To unlock all other extras, input "Game On."
"2K8" and 2K9
Use "Jose Reyes" as a cheat code in "MLB 2K8" to unlock everything in the game. Typing in "Black Sox" to access big head mode is the only cheat code for "MLB 2K9." All of the other hidden features and trophies can only be accessed by completing specific in-game feats such as striking out a certain number of opposing batters or hitting a certain number of home runs in a game.
"2K10"
No specific cheat codes exist for "MLB 2K10," but there are a few in-game cheats that are quite useful. When playing through the season mode, you can alter your players' contracts by going into the "Edit Player" mode and changing the terms of their deals. This will allow you to never lose key players to free agency or to free up some salary when attempting a mid-season trade or attempting to sign new players in the off season. You can speed up the process of bringing a created player up through the minor leagues by decreasing the difficulty in the "Options" menu. When your player reaches the major league, you have to return the difficulty setting to at least pro to be able to unlock any awards or trophies.
"2K11"
Like "2K10," "MLB 2K11" does not have any normal cheat codes. All of the hidden features must be unlocked by achieving certain feats in the game. In this version of the game, achieving these feats gives you points, which can be used to buy the special features.