On the outside, Hyper Zone appears as a massive black cloud with a vaguely-defined central sphere shape. It can spit smaller yet longer tentacle-like clouds to expand its reach, which causes ill effects on living things. It reveals an ominous red eye with a black pupil (most likely Zero) in the introductory illustration.
Hyper Zone's inner environment resembles a big, blue oblivion composed of dark oval splotches sailing through it. In comparison, its counterpart Dark Star in Kirby's Dream Land 3's sequel, Kirby 64: The Crystal Shards, appears as a red oblivion with ribbons of Dark Matter-esque energy.
All the collected Heart Stars coalesce and form the Love-Love Stick. Kirby grabs it and flies into the ominous space above while everyone watches from below.
The blobs in the background move faster with each fight, starting quite slow with Dark Matter, faster with Zero, and extremely fast with 0's eye.
In Boss Butch, Hyper Zone takes on a yellow coloration instead of blue, with blue and red blobs instead of black blobs sailing through it. However, in the Wii U Virtual Console release, the blobs are green and yellow. As with other Virtual Console releases that received specific graphical edits, this change to a more subdued set of colors was most likely made to reduce the likelihood of triggering epileptic seizures.
Hyper Zone has a great similarity to Dark Matter, as depicted in Kirby 64: The Crystal Shards, where its sheer size as a giant cloud mass is shown to nearly eclipse Ripple Star. However, the antagonistic cloud of Kirby's Dream Land 3 was never stated to be Dark Matter itself.
Also in the Guest Star ???? Star Allies Go! mode, when the player selects one of the Dream Friends added in the 2.0.0 update, the floor of the arena when fighting the last three bosses closely resembles Hyper Zone.