Topic: Which ONE Game have you bought the most times?

For me, it is 'Super Mario Bros.'

I've had this Game 7️⃣ times.

I've had it on the:

*NES
*SNES (as part of the 'Allstars' collection)
*GBC
*GBA
*Wii Virtual Console
*3DS Virtual Console
*Game & Watch Handheld (recent colour screen edition)

@BlueGBAMicro
LEGO CITY UNDERCOVER on Wii U, Switch and PS4 (+3DS for the prequel version)

Okami: Ps2, Wii, Switch NA, Switch JPN, xbox one, PC.

Probably Minecraft or Stardew Valley.

Definitely Minecraft. I had it on at least 2 mobile devices, my Wii U, my Switch, and both Java and Bedrock on my PC.

Sonic the Hedgehog on Dreamcast, GameCube, GBA, DS, Wii, 3DS, PC (Steam), iOS, and Switch. Other than Wii U, any device I have I can play the original Sonic the Hedgehog.

Yeah, the GBA port has its problems, but I still like it, allowed me to play Sonic 1 on the go long before the DS, 3DS, and iOS versions.

Edit: worth noting some of these copies were gifts, so I didn't buy all of them.

Minecraft for:

Nintendo Switch
PC (my account broke recently RIP)
Windows 10

Lego Batman. Twice on the Wii, ds, and Xbox 360.

Ocarina of Time or SMB3

Ocarina of Time 4 times.

N64, GCN Master Quest version, Wii VC, 3DS. It's also on NSO+, but I wouldn't count that as a purchase.

Off the top of my head....
World of Goo (Wii, PC, Switch)
Bayonetta (Wii U, PC, Switch)
Shovel Knight (Wii U, 3DS, Switch)
Sword and Soldiers (Wii, Wii U, Switch)

I don't usually rebuy games since I don't replay games, but I remember buying Pokémon Yellow for my Gameboy Pocket (I think it was Yellow) a second time when my Gameboy Color (along with a whole bunch of Pokémon cartridges) was stolen by a bully in Primary Three, or Third Grade in American terms (he never admitted it, never got caught).

Probably Chrono Trigger because I keep falling for Square's lies that if people will buy the re-releases then they might do a new one.

Doom 64 - N64, 2 x Switch (digital, than physical), Steam and Gog because DRM-Free.

Super Mario World - Super Nintendo, GBA, Wii U

Off the top of my head... I don't think I've ever rebought a game myself. I have multiple versions of games, like Ocarina, Majora, Wind Waker, and Twilight's originals and remakes (GCN version of Twilight, not wii), but I never bought the originals, my older siblings or parents did, so I don't count those.

Metroid Prime Hunters (DS twice, Wii U)
Super Metroid (Wii, N3DS, Wii U)
Metroid (Wii, 3DS, Wii U)
Xenoblade Chronicles (Wii, N3DS, Switch)

Not counting any purchases that I've given as gifts, these four are my most bought....Including gifting, I got my little brother a copy of both MPH and Xenoblade Chronicles: DE as well.

Mega Man 2, 3 and 4

NES
GameCube (Mega Man Anniversary Collection)
Wii VC
3DS VC
PS4 (Mega Man Legqcy Collection)

Minecraft (Xbox One Edition, Mobile version)
OR
Portal 2 (I bought it on Xbox One and Switch)

Probably Minecraft.
PC
Xbox 360
Xbox One
PS4
Wii U
Switch
Mobile

The original super mario kart, I have bought this for the SNES, New 3DS, Wii U, Wii, Switch, and on the Snes mini.

I don't think I have missed any (nintendo) platforms that it is possible to play tis game, and still play it at least once a week.