From the Super Mario Wiki
Bullet Biffs (originally known and known in Japan as Gira) are a species of Bullet Bills found in Sarasaland in the game Super Mario Land. Bullet Biffs were only referred to as such in the English digital manual for the 2011 port of Super Mario Land to the Virtual Console, 22 years after the original game's release.
Bullet Biffs look like ordinary Bullet Bills but have rockets on their backs. They can be defeated with a single stomp, earning Mario 400 points. They are only found in the last two kingdoms, Easton and Chai. The launchpads are harmless themselves, much like many other Bill Blasters; however, their machines pop out of pipes in intervals much like a Piranha Plant, rather than the somewhat sporatic firing of their counterparts. The Bullet Biff that comes from them travels with a perfectly straight trajectory as usual, but also moves at a more dangerous speed than an average Bullet Bill. If Mario stands directly in front of the blaster, it will be unable to shoot Bullet Biffs. Some blasters can be used as a stepping stone to reach high areas.
Names in other languages
|Derived from Bullet Bill's Japanese name 「キラー」 kirā ("Killer").