Hornhead is a large, blue beetle, most likely based on the Japanese rhinoceros beetle. It has two horns on the top of its head and one huge horn in front. It has two constantly-glaring eyes, each of which has a purple iris. The beetle's shell is adorned with dark spots and a wavy pattern. Thin legs connect Hornhead's four purple feet to its underside. The mid-boss' shell can open up to reveal a cyan back and two wings.
Hornhead DX looks similar to Hornhead, but with some alterations. Instead of two tiny horns on either side of its head, the enemy has one long protrusion in the center. It has a black head with glaring purple eyes. Its shell and eyelids are gold. The foe's feet and shell patterns are brown. The shell can open to reveal a purple back and two wings.
Hornhead has many attacks. It often begins a battle by rushing at Kirby. If Kirby doesn't get out of the way, the insect will pick him up with its horn and toss him into the top of the screen. If the pink puff dodges this attack, however, the mid-boss will crash into the wall, producing stars for Kirby to use as ammunition and getting its horn stuck in the wall. Hornhead can stick its horn into the ground and unearth it, tossing a rock (or two) across the stage.
Hornhead has several horn-based attacks that it can use with little to no warning. It may thrust upwards once, thrust forward once, thrust forward thrice in rapid succession, or unleash a flurry of slashes before finishing off with a strong thrust.
At low health, the mid-boss may lift off the ground and zigzag across the plane, darting from foreground to background repeatedly. When it reaches a wall, the mid-boss may turn around and zigzag back. It will eventually collide with a wall, dropping a star. When Hornhead's horn glows bright blue, it will launch a cutter beam (that produces a star when it touches the wall); it can fire up to three in rapid succession, aiming them straight across the ground or into the air.
Hornhead DX is much smarter than Hornhead. It often uses Hornhead's last-resort attacks and even combines moves (such as two horn swipes followed immediately by a flurry of slashes). The mid-boss can charge up and fire two cutters at once, with one traveling horizontally and one firing diagonally upwards. At low health, Hornhead DX will fly around. It can fire up to three cutters from the air but will otherwise act similarly to Hornhead. It can now use its two horn swipes, a flurry of slashes, and a fast cutter attack back-to-back. The mid-boss can also fly directly over Kirby and plunge into the ground, launching a rock when it unearths its horn.
- Hornhead's appearance seems to pay homage to Bugzzy, a classic beetle character in the Kirby series.
- The sound heard toward the end of Hornhead's cutter attack is that of a Como dropping when approached by Kirby.