From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Mutant Namekians are the children that Piccolo Daimao births and belong to Piccolo Daimao's Demon Clan. It is said that the evil spirit of Piccolo Daimao warps them into horrible mutants. These creatures are the first Namekians to appear onscreen in the anime and debut in "Enter King Piccolo". All of the known Mutant Namekians have names based on musical instruments.
Sometime after coming into being, Piccolo Daimao spawned several Mutant Namekian children. They all had a similar winged and scaled appearance. Unlike Piccolo Daimaos's later sons, such as Drum and Piano, their names were not revealed in the anime and they never spoke.
Those killed by members of Piccolo Daimao's Demon Clan spent an agonizing eternity trapped in Limbo rather than being sent to the Next World. Turtle Hermit recounted how these creatures had rampaged throughout the world until they attacked Mutaito and his students. In the aftermath, all of the creatures were destroyed, however, Crane Hermit, Turtle Hermit, and a wounded Mutaito were the only survivors of their school.
Three other named Mutant Namekians appeared in Daimaō Fukkatsu – Banjō, Orugan, and Ukulele – alongside Cymbal, Drum, and Tambourine. Ukulele was a green Gargoyle/Platypus-like Mutant Namekian with Pteranodon features (like Piano). He could either attack with his tail, a sword, or the Chou Makouhou. Banjō looked like a humanoid version of Octopapa. He was first encountered as a boss character in the Pirate Cave and later reappeared as a regular enemy. Banjō's techniques were the Revolving Attack and the Hasshu-ken. Orugan was a pink, alien-like Mutant Namekian and Piccolo Daimao's personal aide in the video game similar to how Piano was in the manga.
Six other named Mutated Namekians appeared in Gokū Den – Hāpu (a blue Tambourine type), Mandorin (a red Tambourine type), Beru (a teal Cymbal type), Marinba (a dark-blue Cymbal type), Biora (a blue Drum type), and Konga (a grey Drum type) – alongside Cymbal, Drum, and Tambourine.
Drum, Tambourine, and Ukurere were enemy and playable characters in Dragon Ball: Advanced Adventure. Maraca, a Tambourine-like Mutant Namekian sans wings, also appeared as an enemy character.
In Dragon Ball Online, the Mutant Namekians reemerged due to the refugee Namekians' breeding spot being in close proximity to Piccolo Daimao's Throne. Poko Priests could summon Mutant Namekians to do their bidding. The fin and horn styles of Drum and Tambourine were also available to normal Namekians.
Known Mutant Namekians