suppermariobroth:

Small comic illustrating a glitch in the Japanese Super Mario Bros. 2, known internationally as Super Mario Bros.: The Lost Levels, from the Japanese Family Computer Magazine. If Mario follows Bullet Bills without letting them leave the screen, the console will not have enough space in memory to spawn the enemies that would otherwise appear.

In the upper panel, Mario is following two Bullet Bills and notices that the Hammer Bro that would otherwise be in this spot is missing. In the lower panel, the same happens with a Piranha Plant when Mario is following three Bullet Bills at once.

_{Main Blog | Source: Family Computer Magazine (Japan), Issue 25, 1986}