|Home world:||Planet Earth,Tokyo Bay|
|First appearance:||Return of Ultraman episode 1 "All Monsters Attack" (1971)|
|Affiliation:||Beryudora (Body part)|
Subtitle: Sludge Monster (ヘドロ怪獣, Hedoro Kaijū?)
- Height: 50 m
- Weight: 12,000 t
- Origin: Tokyo Bay
Return of Ultraman
Zazahn was one of two aquatic monsters that rose from the depths of the ocean along with Takkong. The two monsters battled at once, smashing through nearby structures in Tokyo Bay. During the midst of their fight, a young man known as Hideki Goh was killed while he was rescuing lives from the two monsters' destruction. Zazahn and Takkong continued their titanic war, until finally the battle ended with Zazahn being beaten to death by Takkong.
- Suit Actor: Eiichi Kikuchi.
- Zazahn's debut was coincidentally at the same time of the release of the Toho film, Godzilla vs. Hedorah. This is most likely done to propagate the serious pollution crisis that was plagueing Japan at the time of the episode's airing.
- Curiously, Hedorah and Zazahn bear a close resemblance to each other, although Zazahn appears to be made of plants while Hedorah's texture is vaguely plant-like instead.
- Although not physically seen, Zazahn is one of the monsters that makes up Beryudora's left arm in Mega Monster Battle: Ultra Galaxy Legend The Movie.
- Zazahn may have inspired The☆Ultraman kaiju Red Smogy.
Powers and Weapons
- Adept Swimmer: Being completely composed of seaweed, Zazahn is fully capable even if underwater.
|Return of Ultraman Kaiju & Seijin|
|Takkong | Zazahn | Arstron | Sadola | Detton | Kingsaurus III | Gudon | Twin Tail | Gorbagos | Ghostron | Dangar | Stegon | Mognezun | Shugaron | Seamons | Seagorath | Eledortus | Terochilus | Bemstar | Sartan | Magnedon | Beacon | Gokinezula | Zanika | Vacuumon | Kupukupu | Kingstron | Zagorath | Nokogilin | Gronken | Varricane | Yadokarin | Oxter | Plooma | Alien Zelan | King Maimai | Alien Mates | Muruchi | Leogon | Pris-Ma | Draculas | Re-Seagorath | Re-Bemstar | Black King | Alien Nackle | Alien Varduck | Alien Black | Snowgon | Alien Baltan. Jr | Builgamo | Alien Stora | Paragon | Alien Grotes | Kodaigon | Granadas | Alien Centaurus | Robonez | Alien Cygnus-61 | Alien Messie | Alien Zoole | Red Killer | Femigon | Yametaranese | Sasahiller | Alien Ateria | Alien Mysteler | King Bockle | Alien Bat | Zetton II|