HR-D3

"An ancient war machine that somehow drifted into this universe from another dimension. What a dream battle!"

- VS HR-D3

HR-D3 is a giant mechanical construct that looks vaguely similar to King Dedede. It is best known for debuting in released material for the unreleased Kirby GCN.

Physical Appearance
HR-D3 is a giant robot built in the likeness of King Dedede. Rather than the bulky appearance of the previous model, this robot is more streamlined in design and is outfitted with more weapons. It bears a similar drill for a hand, but has a giant laser cannon hidden inside its neck. It has painted patterns that somewhat resemble Dedede's robes, and has his trademark "peace" symbol on its chest. The HR part of its name might stand for "Halcandra Robot," but it is likely a reference to HR-E. The D3 part is a reference to King Dedede.

The version appearing in Egg Engines is different in coloration, and its interplanetary appearance implies that the ancient civilization of Halcandra initially created it. Its design is slightly different; its color palette being changed to reflect Metal General EX's, and even having Metal General EX's head as its symbol instead of King Dedede's peace symbol. Other than a new paint job, however, this incarnation of HR-D3 is otherwise identical to the other except for having the Metal General inside its cockpit.

Kirby GCN
HR-D3 was set to debut as a boss in the cancelled GameCube title Kirby GCN. It would have been fought with the camera angled, focusing slightly more on its side, and the characters fighting it were shown minimized. Characters could travel behind it, as evidenced by Kirby in the game's trailer. It is unknown whether or not it would've been fought like this the entire battle.

Kirby Mass Attack
HR-D3 made its official debut in the series as a cameo in Kirby Mass Attack. It was the boss of Chapter 2 of the sub-game, Kirby Quest, and had a staggering 2500 HP. It can hit the Kirbys with its drill (an attack that KOs four Kirbys), or fire a giant orange laser from its mouth (which KOs six Kirbys). It is fought in the same arena as King Dedede himself. HR-D3 is given its Kirby GCN design, likely as a reference to the cancelled game.

Kirby's Return to Dream Land
HR-D3's appearance in Kirby Mass Attack was merely a precursor to a much larger role in the Extra Mode of Kirby's Return to Dream Land as the "second" boss of Egg Engines, where the beaten Metal General EX interfaces with it in order to defeat Kirby.

HR-D3 mainly attacks by slamming its giant fist and drill into the ground. The war machine will also regularly fly out of range to do one of three things: Either to shoot eye lasers in a wide arc, having its pilot open its cockpit to rain down missiles on Kirby, or to heat up its weaponized arms and spin them around on the ground. Note that in this phase, it is very similar to HR-H, whom is HR-D3's namesake.

After its surprisingly small health meter is depleted, HR-D3 is seemingly defeated and sinks off-screen. But seconds after this happens, the robot revives itself and comes back, revealing its second "true" shell. HR-D3 gains new attacks in this brutally beaten form, such as body slamming Kirby, once again trying to punch and impale Kirby (the latter sometimes being electrified and therefore dealing more damage) which is now performed three times in a row, an aerial version of its heat sweep attack, and lastly firing its gargantuan trademark laser cannon in its chest that does severe damage if not avoided; HR-D3 also has much more health during this second battle, and will sometimes fly into the background to use its laser and missile attacks it used in its first phase. Throughout the battle, he loses more parts based on the amount of damage he takes (similar to Robo Dedede in Scope Shot), until becoming nothing more than a steel-frame skeleton, two headlights, and an engine. After being defeated once more, the arms explode and the metallic monstrosity and its power-crazed pilot are taken down for good.

Trivia

 * With no fewer than two health bars, HR-D3 has arguably the highest amount of HP in Kirby's Return to Dream Land if Magolor's two forms are considered separate bosses.
 * HR-D3 is the only boss to first appear in Extra Mode and to not appear in the Main mode of Kirby's Return to Dream Land (Galacta Knight not being counted, as he only appears in The True Arena).
 * The laser HR-D3 fires in Kirby's Return to Dream Land and the Kirby GCN trailer is blue, while the laser it fires in Kirby Mass Attack is orange.
 * The VS Quote for HR-D3 states that it drifted into Egg Engines from another dimension.
 * In the first part of the battle, Grand Doomer's battle music is heard, while in the second part, Landia's is heard.
 * The Hoshi no Kirby 20th Anniversary Encyclopedia dubs the Kirby GCN / Mass Attack appearance of this robot "Dedede Robo" (デデデロボ), which is identical to the Japanese name of Robo Dedede.