GAME GENIE CODES: T.

 T2 the Arcade Game
 Target Earth
 Task Force Harrier EX
 Tatsujin
 Taz Mania
 Techno Clash
 Technocop
 Tecmo Super Bowl
 Teenage Mutant Ninja Turtles - Hyperstone Heist
 Teenage Mutant Ninja Turtles - Tournament Fighters
 Terminator
 Terminator 2 Judgment Day
 Thunder Blade (see Super Thunder Blade)
 Thunder Force 2
 Thunder Force 3
 Thunder Fox
 The Tick
 Tiny Toons Adventures - Buster's Treasure Hunt
 Toe Jam & Earl
 Toe Jam & Earl in Panic on Funkotron
 Toki
 Tommy Lasorda Baseball
 Toy Story
 Trampoline Terror!
 Triple Score
 Trouble Shooter
 Truxton
 Turrican
 Twin Cobra
 Two Crude Dudes

GAME GENIE CODES: U.

 Ultimate Qix
 Urban Strike
 USA Basketall World Challenge

GAME GENIE CODES: V.

 Valis 3
 Vapor Trail
 Vectorman
 Virtua Racing
 Volfied
 VR Troopers

GAME GENIE CODES: W.

 Wardner
 Warlock
 Whip Rush
 Wolverine-Adamantium Rage
 World Championship Soccer
 World of Illusion starring Mickey Mouse & Donald Duck
 World Series Baseball
 WWF Super Wrestlemania

GAME GENIE CODES: X.

 X-Men
 X-Men 2 - Clone Wars

GAME GENIE CODES: Y.

 Ys3 - Wanderers from Ys

GAME GENIE CODES: Z.

 Zany Golf
 Zero Tolerance
 Zombies Ate My Neighbours
 Zoom!