One of the more
common but best Mario multi-carts to own is this
one.
The reason is because it
contains every one of the 8-bit Super Mario games, plus
extras.

Did the label artist run out of Mario-related
pictures?
The games on this multi-cart contain those you'd
expect: SMB, SMB2 (known as Super
Mario USA in Japan) and SMB3. But coming
from Asia as the majority of multi-carts do, this
also contains the very popular SMBj, which
was only released in the Asian market. There's two
other bonuses on this cart, a game known to American
Famicom gamers as "Baby Mario" and another called
"Super Mario 4."
Super Mario 4 is just a hack of the
Famicom game Armadillo. Mario is inserted in
place of Armadillo, the games main character. The
hack is poor in the sense that having added Mario
the gameplay is, for the most part, in slow motion.
But one cool feature is seeing Mario turn from his
regular self into a ball, like Armadillo would.

The front of the box with the cartridge inside.

The back of the box.
Here's the games list:
New Super Mario “4” (Rock & Ball Mario)
[Armadillo hack w. Mario]; Super Mario 3 (Flying
Racoon); Super Mario 2 (American Version); Super
Mario 2 (Japanese Version); Baby Mario; Doctor
Mario; Super Mario; Mario Bros; Mickey Mouse;
Bowling.