Guard

Guarding is Kirby's only defensive action in games such as Kirby Super Star, its remake, Kirby's Return to Dream Land, Kirby's Dream Collection: Special Edition, and Kirby: Triple Deluxe. By holding down the guard button, Kirby assumes a defensive posture until the button is released. While guarding, Kirby takes no damage from weak attacks and minimal damage from stronger attacks, in addition to retaining his ability and not getting knocked off the ground. Enemies that come in contact with a guarding Kirby also take minimal damage.

Generally, guarding is ineffective against attacks which involve grabbing. Guarding also has no effect on environmental elements such as wind or lava. Kirby can only guard while standing still.

Abilities with Special Guards
Bell - In Kirby: Triple Deluxe, guarding with the Bell ability causes Kirby to pull the bell he wears on his head over his body to protect himself. When attacked while guarding, the bell will send out sound waves that hurt nearby enemies.

Ice - In Kirby's Return to Dream Land, guarding with the Ice ability produces a spherical ice formation around Kirby which blocks more damage than a regular guard. It also damages nearby enemies when the guard button is released. This ability is also present in Kirby Super Star and its remake.

Leaf - In Kirby's Return to Dream Land, while guarding with the Leaf ability, Kirby is intangible instead of invincible; attacks will simply pass through him regardless of their power. This guard also makes Kirby immune to grabs. Releasing the guard causes minor damage to nearby enemies.

Mirror - In Kirby Super Star and its remake, guarding with the Mirror ability provides a shining bubble of energy around Kirby's body. This bubble negates damage from even strong attacks and can reflect projectiles.

In the Super Smash Bros. series
The shield mechanic in the Super Smash Bros. series is heavily based on the guard mechanic of the Kirby series. Shielding in the Super Smash Bros. games produces an energy bubble very reminiscent of the Mirror ability's Reflect Guard. The primary difference is that shields shrink as they are held or when they take damage, and will break if they get too small, stunning the user, though shields' power regenerates when they are not in use.

Kirby: Triple Deluxe
The Guard mechanic was vastly upgraded in Kirby: Triple Deluxe. Not only can players guard, but they can also perform a dodge while guarding, making Kirby: Triple Deluxe's guard system very similar to Super Smash Bros..

In Kirby Fighters, guarding has limited time and improved dodging, making it further similar to Super Smash Bros.. Kirby's can also perform a perfect guard and an autoguard (requires Easy or Very Easy handicap)

Trivia

 * As a helper, TAC has his own guard move known as "TAC Hide". When used, it allows attacks to pass right through him, leaving him completely unscathed.