Octacon is the first of many monsters that Kirby fights in the anime series, appearing in the very first episode, Kirby Comes to Cappy Town. When Kirby crash-lands on Dream Land, Dedede buys this little guy as a pet and keeps it in a tank in the throne room. In the beginning, sheep from Dream Land's pasture occasionally go missing. As time goes on, the disappearances become much more frequent and bones are found scattered throughout the fields. It soon becomes apparent that Dedede's "pet" is responsible for these mysterious disappearances. Octacon grows to epic proportions and starts going on a rampage in King Dedede's Castle. Apparently, Dedede did not even know that Octacon was doing these actions or even growing bigger to eat, as he tried to file a complaint to Nightmare Enterprises due to the fact that, despite ordering a giant octopus monster, he "ended up with a wimp." Octacon later placed Dedede under mind control to kill Kirby, although it was broken after the brainwashed Dedede ran into a pillar. When he saw the size of Octagon, he also demanded for his manservant, Escargoon, to contact Nightmare Enterprises and fetch his pocketbook so he could demand a refund. With Dedede's castle becoming destroyed by the titanic octopus the Cappies seemed hopeless. Octacon attacks by creating hordes of flaming small octopi (that look much like the smaller Octacon), whipping things around with its long and supple tentacles, and by shooting fire. It also possesses strange hypnotic power, which he uses to make King Dedede attack Kirby. The Star Warrior inhales Octacon's mini octopi and becomes Fire Kirby- marking the first ability seen in the series. Kirby lets loose a stream of fire and destroys Octacon.
Octacon starts off as a little pink octopus minding its own business floating around in Dedede's royal fish tank. When Octacon reveals its true form, it grows in size and appears similarly to a more menacing version of Flotzo. Octacon is so big he nearly dwarfs Dedede's castle. It has dark red skin and sunken in green eyes. In its smaller form, those eyes are black dots, unless it stares into a potential victim's eyes, in which case it is using its hypnosis with its eyes glowing green. He attacks with smaller octopi that are engulfed in a pinkish-red flame.