Hammer (Martillo in Spain) is one of Kirby's special Copy abilities, first appearing in Kirby's Adventure. It has very limited range, but is the heaviest hitter among his normal abilities - most normal enemies are instantly K.O.-ed in a single hit. When used on a mid-boss or regular boss, the moves simply do very heavy damage. Its high damage makes it very desirable in Boss Endurance events.
The hammer Kirby wields looks similar to King Dedede's mallet, with a shorter handle. Hammer is one of the few abilities that can not be found by inhaling a common enemy. It is most commonly obtained from Bonkers the mid-boss. Otherwise it can be obtained via Mix, the Copy Pedestal behind the golden door in Kirby & the Amazing Mirror, or by finding the Copy Essence Deluxe in Kirby Super Star and Ultra. Orange Dygclops from Heavy Mole also give Hammer.