Masked Dedede

Masked Dedede is an alter-ego of King Dedede who wears a metallic mask to cover his face. He first appears in Kirby Super Star Ultra as the final boss of the Revenge of the King game. He has reappeared as a boss in Kirby: Triple Deluxe and Kirby's Blowout Blast, and as King Dedede's Final Smash in Super Smash Bros. Ultimate. Masked Dedede also has his own unique theme, which is heavily based on King Dedede's theme in Kirby no Kirakira Kizzu.

Kirby Super Star Ultra
In Kirby Super Star Ultra, Masked Dedede only appears at the end of Revenge of the King, serving as its final boss. He fights similarly to his normal form, but his attacks are more powerful. One notable change is that he doesn't flinch during some of his attacks, such as the Head Slide. His hammer causes Kirby to become electrified if hit, and if he jumps before swinging his hammer, it'll unleash a shockwave that travels across the ground. He performs his Super Dedede Jump three times in a row in quick succession, similarly to how he does in Kirby's Dream Land’s Extra Mode. Masked Dedede can also float or inhale and spit Kirby out, but these are unchanged from King Dedede's; when he does his inhale, however, his mask is lifted off his face. In addition to performing more powerful versions of his older attacks, he also has brand new ones. He can set his hammer down, with its spike in the ground like a stake, and open up its head like a hatch, and either shoot three missiles or spew out flames. He can also perform the Giant Dedede Swing, his equivalent to Kirby's Hammer Swing. Masked Dedede starts spinning his hammer and rushing forward before spinning very quickly and homing in on Kirby; he is invincible when performing this attack. After spinning for a while, Masked Dedede will become dazed for a brief period of time, with his mask hanging to the side of his face.

To make the battle tougher, the Dedede Arena is now in a caged boxing ring, with the cage being electrified. This makes flying to avoid his attacks more risky, and can also cause Kirby to lose his ability star if he drops it.

Upon defeat, Masked Dedede's mask shatters in a similar manner to Meta Knight near the end of Revenge of Meta Knight. King Dedede is sent flying in an identical fashion to when he lost in Spring Breeze. He is seen in the ending credits dejectedly walking through a desert under a setting sun, in the company of his Waddle Dees. This scene also parallels the ending of Revenge of Meta Knight when Kirby and Wheelie rode through the desert under the setting sun.

Kirby: Triple Deluxe
As Kirby confronts Taranza at Royal Road, Taranza uses mind control on King Dedede, during which the mask flies onto King Dedede's face. The battle then starts with Masked Dedede swinging his hammer twice before slamming it into the ground. Masked Dedede has the same set of moves as he did in Kirby Super Star Ultra except for the Giant Dedede Swing. Masked Dedede will no longer flinch from being attacked, and upon inhaling Kirby, will spit him at the screen and cause him to drop his ability; Masked Dedede's inhale is also more powerful than before, reaching across the arena, but Kirby will only be in danger if he gets too close. After being defeated, his hammer explodes and part of his mask has been destroyed. Taranza appears briefly shocked, but then uses his magic again to further strengthen Masked Dedede, changing his red colors to purple. Masked Dedede, now under the name Masked Dedede's Revenge, grabs one of the decorative axes and destroys the remaining ones using a magical attack. Masked Dedede's Revenge uses the same attacks as Masked Dedede except for the missiles and flamethrower, as he no longer has his mechanical hammer. However, he also has new powerful moves. Masked Dedede's Revenge can now perform the Giant Dedede Swing, which speeds up faster than its previous version; like before, he becomes dazed after finishing this move, leaving him vulnerable. He can go to the side of the arena and shoot two magical projectiles, with the first arcing upward and the second traveling straight. He can still perform his head slide, although he sometimes performs it twice consecutively (turning around after the first if needed). He can use his axe like a helicopter and try to ram Kirby from the background and foreground before landing; this attack also leaves him dizzy. His Super Dedede Jump now causes shockwaves on both sides of him. He can imbue his axe with fire, leap upwards, and slam it into the ground from the background, causing an explosion. He can jump and hover in one of the corners of the arena before shooting nine magical projectiles across the ground. He can also swing his axe like he did his hammer before; the grounded and aerial versions both produce a shockwave.

After reaching half health, Masked Dedede's Revenge will start rapidly swinging his axe in Kirby's direction, performing a spin halfway through the move and his first opportunity to turn around if Kirby gets behind him. After this, he thrusts his axe forward across the arena; he can turn around beforehand if needed. Taranza can assist Masked Dedede's Revenge from the background by tossing him dark balls of energy that he can deflect to hit Kirby. Taranza can also produce a giant dark energy ball that, upon being hit by Masked Dedede's Revenge, bounces on the floor and ceiling of the arena before being hit again and exploding upon impact. After this, he will start reusing the same moves from his first phase.

Dedede's Drum Dash Deluxe
The Masked Dedede Mask appears as an unlockable Mask in Dedede's Drum Dash Deluxe. It is unlocked after beating every normal level.

Kirby's Blowout Blast
Giant Masked Dedede is the final boss of Kirby's Blowout Blast, appearing at the end of the Secret Path. He does not appear during the first phase against King Dedede's Revenge, instead appearing once King Dedede's Revenge is revived by a Sparkling Star. Like Masked Dedede in Kirby Super Star Ultra, he uses powered-up attacks from Giant King Dedede/Giant King Dedede's Revenge, in addition to some new moves. He can use his hammer to create a giant heat laser that he shoots from above, or he can shoot a bunch of missiles; unlike before, his hammer opens up by having the head split in half instead of opening like a hatch. When inhaling, his mask opens up instead of being lifted above his head; while inhaling, he also inhales many Gordos that Kirby has to jump over. In addition to these new attacks, Giant Masked Dedede's mask protects him from Kirby's Star Spit, forcing him to use Blaster Bullets in order to damage him.

Kirby Battle Royale
In Kirby Battle Royale, the Masked Dedede Mask appears as an unlockable headgear for King Dedede. It is unlocked by scanning a King Dedede amiibo. King Dedede wears the mask and wields Masked Dedede's signature hammer upon using this headgear. Additionally, Hammer Kirby's alternative headgear has the hammer's design to change to resemble Dedede's own hammer.

Super Smash Bros. Ultimate
In Super Smash Bros. Ultimate, Masked Dedede is featured in King Dedede's Final Smash, Dede-rush. Upon hitting an opponent with his mallet, said opponent will be forced into a caged boxing ring and hit by a barrage of missiles. Masked Dedede will then perform his Giant Dedede Swing and slam into his opponent, destroying the cage and sending them flying.

Masked Dedede also appears as a primary, ace-class attack spirit, which depicts his artwork from Kirby Super Star Ultra. His spirit sports no effect when applied to a fighter.

Physical appearance
Masked Dedede appears identical to King Dedede except he wears a grey, metal mask with three golden horns and two smaller gray horns, along with a bottom piece that covers his chin, separated from the other part of the mask by a jagged line. He also wields a different hammer than before, dubbed the "brand-new Dedede Hammer." Instead of wielding a wooden mallet, he wields a mechanical hammer. The hammer is mostly blue in color, but features alternating red and yellow triangles near the head, which is silver and feature's King Dedede's icon on it. The handle appears longer and features a spike on the bottom of it along with one of the top of the hammer. On the back of the hammer is a jet.