Strider
"Strider," for the NES features an elite military organization in the future and puts you in the shoes of Strider Hiryu, the youngest ever strider. You are charged with assassinating a fellow strider who has been captured by an enemy organization and is considered a liability. You can input the following cheat codes to gain access to all the game's levels: "AAIA AAAA AAIA" for Level 1; "BCJB BBNB NBAB" for Level 2; "CEOC KCOC OCMC" for Level 3; "DGPD LDBD BDAD" for Level 4; "HLDJ PIGH GHCH" for Level 5; "HLDJ DIGH GHGH" for Level 6; "HLEJ DIGH GHHH" for Level 7; "INHK GJHI HILI" for Level 8; "JPIL HKIB IBMJ" for Level 9; "CJBE ADBO BONC" for Level 10; "BJAP PEAN ANOB" for Level 11; and "DMCC BGCP CPOD" for Level 12.
Contra
"Contra" is a legendary run-and-gun action game, released on the NES by the Japanese developer Konami in 1988. The game was known for its challenging difficulty, and the developers included a number of input codes to help frustrated players. Input "Up," "Up," "Down," "Left," "B," "A," and "Start" at the title screen to receive 30 lives. In addition, you can steal life from your partner when playing two-player mode by holding down "A" and "B" when you die.
Castlevania II: Simon's Quest Cheats
In "Castlevania II: Simon's Quest," an exploration-based action platformer for the NES, you direct Simon Belmont in his quest to defeat Dracula. As with all the original "Castlevania" games, completing the game can present a challenge. Developers included a number of cheat codes to aid players at their wit's end. Type in "7MEF 0VFT 151Z Y2Z5" to go straight to the fight with Dracula. Input "DY31 LXDY W45X TGJX" to automatically defeat Dracula. Type "UGKD N3BV W2VL SDYV" to fight Dracula for the game's best ending. Finally, type "MLIT WVCW T3KU SFZC" to start the game with all items and weapons.
Teenage Mutant Ninja Turtles II: The Arcade Game
In "Teenage Mutant Ninja Turtles II: The Arcade Game" for the NES, you explore, jump, and fight your way across two-dimensional, multi-level landscapes to rescue Splinter and April from the malevolent clutches of the evil Shredder. To access extra lives with stage select, go to the title screen and input "B," "A," "B," "A," "Down," "B," "A,2 "Left," "Right," "B," and "A." To get extra lives without the level select option, input "Up," "Right," "Right," "Down," Down," "Left," "Left," "Left," "Left," "B," and "A"