Breath of the Wild, but I am surprised Wii Sports isn’t an option considering it was vastly more popular than Twilight Princess and commercially speaking the most successful launch title in history.

Because it was novel, accessible, and fun.

Controlling a video game with movements was a new and exciting concept that felt downright futuristic at the time, and Wii Sports' simple, pick-up-and-play style allowed people who'd never even played a video game to quickly learn and enjoy it.

As a result, it became a highly social game, a centerpiece of parties and family gatherings, which added to the fun as people laughed and cheered each other on and passed the Wiimotes around so everybody could have a go. It brought people together; young and old, male and female, those who'd gamed before and those who hadn't.

Mario 64, simply because it was the most revolutionary game in history. It changed gaming.

I wouldn't say games like SMW, Sonic Adventure, Soul Calibur, BotW, or whatever. They're absolutely great games but I feel a great launch game should justify the upgrade to new hardware (offer something you can't find similar anywhere else). Also Halo is disqualified because it's on Xbox.

SM64 and Wii Sports were kinda like "Oh my God! This is the future!" like experiences. Other consoles had moments like that but not many consoles launched with games like that on day one.

Super Mario 64, it was revolutionary.

Super Mario 64 hands down...

The 'greatest' game in terms of what I would most want to play: BotW

The launch title that I feel had the greatest impact on gaming: Super Mario Bros

Wii Sports

Going to have to go with Halo.

While SMB made a huge impact, with Nintendo's continued presence, it had a lot of support with it, and didn't launch with the Japanese Famicom launch.

Wii Sports was also big, but the games today are nothing like Wii Sports. Wii Sports started a brief movement.

Halo's impact has continued presence in today's gaming scene. Halo spawned Halo 2, and Halo 2 spawned the multiplayer movement. While it didn't do it first it certainly brought a lot more attention to it. Many of the top games today are FPS with multiplayer elements much like the Halo series. Halo helped MS succeed, MS becoming a 4th player in the console space and to hold 3rd place throughout most of it's lifetime. MS succeeding helped create XBL, and XBL is the cause of PS plus price and Nintendo online. Due to one game, many people are now paying to play online. Halo's launch buddies were absolutely terrible too.

Breath of the Wild? Didn't really do anything but help one console so far, maybe in the future we will look back and see BoTW as the beginning of a huge movement though.

What the heck? Where is Tetris?