Mechanical Beasts

The Mechanical Beasts, also known as Kikaiju (機械獣) are Dr. Hell's primary force in Mazinger Z. In the manga, the Mechanical Beasts are found underground nearly intact and modified. In the anime, Dr. Hell built them from scratch from the remains of the original models. The Japanese pronunciation comes from the words kikai and kaiju.

History
The Mechanical Beasts were found in an expedition led by Juzo Kabuto on the Greek Island Bardos. The scientists discovered that these large machines were built to protect the island inhabitants against invaders. The scientists rebuilt these large constructs to study them further. But one of the scientists was planning to use them to gain control of the world. He used the machines to massacre the scientists so that no one would stand against them. But Prof. Kabuto survived and used schematics from the machines to build his own robot, the Mazinger Z to combat Dr. Hell who planned to kill him.

General Design
The Mechanical Beasts were generally made from steel and powered by atomic energy (some of them were equipped with sturdier armor and even fewer used Japanium based weapons and armor). While these giant monsters could easily overpower military weapons, they were little match for robots composed of Super Alloy Z with offensive weaponry. To get around this Hell often had to use gimmicks like aerial and aquatic Mechanical Beasts to out best the Mazinger, that is until the Mazinger became outfitted with special equipment to reduce these weaknesses.

Some Mechanical Beasts usually just use limited AI in battle, but in rare occasions they are either piloted or remote controlled. In even rarer cases, the Mechanical Beasts show autonomy such as refusing to fight or preserving honor. Mechanical Beasts are armed with several weapons and equipment depending on how they were built and their situation.

Ghost Mechanical Beasts
The Ghost Mechanical Beasts appeared in the Mazinger Z anime and the manga published by TV Magazine and by Gosaku Ōta alongside Archduke Gorgon. They are more advanced versions of the Mechanical Beasts featuring organic body parts and appear to be prototypes of the Warrior Beasts in Great Mazinger. Compared to the regular Mechanical Beasts, the Ghost Mechanical Beasts feature more powerful weaponry and better reaction time. However they possessed no sentience compared to the Warrior Beasts. Their naming includes a Greek letter and a Latin number (or Roman numerals) after their given names. While they were never seen in the original manga, they were added in supplementary related materials such as Mazinger Z: Mycenae no Densetsu no Maki.

Manga
{{Template:Scroll box||content = ====Original====
 * Garada K7
 * Doublas M2
 * Dogla S1
 * Magla F2
 * Bazin B9
 * Bamaras Y1
 * Unnamed Doppelganger Mechanical Beast
 * Ozones B3
 * Dayan N4
 * Demos F3
 * Abdora U6
 * Gromazen R9
 * Goronko S2
 * Mario N7
 * Crocodiver O1
 * Grogos G5
 * River F9
 * Danube α1
 * Ghostfire V9
 * KingDan X10
 * Toros D7
 * Belgas V5
 * Glossam X2
 * Birdon B7
 * Jeiser J1
 * Hell King Gordon

TV Magazine

 * Gokyun U5
 * Fubuking S1
 * Deathtokiller G7
 * Baron Ashura (Mecha)
 * Bossman B9
 * Great Bardon
 * Urah P9
 * Naidol V1}}

Anime
{{Template:Scroll box||content = ====Toei====
 * Garada K7
 * Doublas M2
 * Gromazen R9
 * Gaia Q5
 * KingDan X10
 * Zaila
 * Danchel
 * Ozones B3
 * Abdora U6
 * Demos F3
 * Dayan N4
 * Brighton J2
 * Bicong 09
 * Goronko S2
 * Modilus
 * Spartan K5
 * Chigul E7
 * Gorias W3
 * Balcan P5
 * Holzon V3
 * Glossam X2
 * Devila X1
 * Stronger T4
 * Wainder A2
 * Balanger M1
 * Balanger M2
 * Damdam L2
 * Jinrai S1
 * Aeros B1
 * Aeros B2
 * Aeros B3
 * Daima U5
 * Belgas V5
 * Hogas D5
 * Grengus C3
 * Brutus M3
 * Megaron P1
 * Megaron P2
 * Megaron P3
 * Gelbros J3
 * Baras K9
 * Genocider F9
 * Deathma A1
 * Glanada E3
 * Rockron Q9
 * Archerian J5
 * Zarigan G8
 * Grader F3
 * Kirma K5
 * Deltan V8
 * Gyron J1
 * Rood R2
 * Bazila F7
 * Blazas S1
 * Blazas S2
 * Mandra M3
 * Basara Q5
 * Kajimof T7
 * Gumbina M5
 * Briver A3
 * Dagan G3
 * Bazuson M1
 * Faizar V1
 * Jeiser J1
 * Blogun G3
 * Satan Claus P10
 * Yubrin T9
 * Balmos Q7
 * Titan G9
 * Giant F3
 * Descross V9
 * River F9
 * Rhine X1
 * Nitan 03
 * Fangas B7
 * Devil Chief A7
 * Marion P3
 * Jenoba M9
 * Mondos Q3
 * Skeleton O7
 * Minos M7
 * Apollo A1
 * Serpenter I6
 * Blaster A7
 * Jetfire P1
 * Blacker F2
 * Triple L5
 * Hawk Y2
 * Chickeron N9
 * Rayas D5
 * Bornest S9
 * Glory R2
 * Harkenschmitt X9
 * Klasbas P9
 * Haribiyun V6
 * Saiga O3

Ghost Mechanical Beasts

 * Gusios βIII
 * Unicorn Σ2
 * Kentol Γ7
 * Harpia Π7
 * Drago Ω1
 * Elephans γ3
 * Greeks ΨII
 * Poses OII
 * Parlas ΔV
 * Gilania β5

Mazinger Z vs. Devilman

 * Zaurus F1
 * Bragger S1
 * Demonger J5
 * Mantes K9
 * Baian S2
 * Purimas W5
 * Barias B5
 * Dankimas C2
 * Elkines K2
 * Barbados F7
 * Ghostarm V10
 * Toros D7
 * Headhawk M3
 * Magudas J9
 * Scarald B7

Mazinkaiser

 * Garada K7
 * Doublas M2
 * Gaia Q5
 * KingDan X10
 * Danchel
 * Abdora U6
 * Dayan N4
 * Goronko S2
 * Chigul E7
 * Stronger T4
 * Brighton J2
 * Grossam X2
 * Bazin B9
 * Bamaras Y1
 * Ghostfire V9
 * Aeros B2
 * Jinrai S1
 * Baras K9
 * Balanger M2
 * Jenoba M9
 * Kajimofu T7
 * Demonger J5
 * Birdon B7
 * River F9
 * Ashura Mazinger
 * Damdam L2
 * Crocodiver O1
 * Yubrin T9
 * Toros D7

Ghost Mechanical Beasts

 * Drago Ω1
 * Venus A (Post-transformation)
 * Gusios βIII
 * Elephans γ3
 * Triple L5
 * Hawk Y2
 * Parlas ΔV
 * Garadoubla MK01
 * Hell King Gordon}}

Other

 * Unnamed Ram-like Mechanical Beast: appeared only in a flashback during UFO Robot Grendizer vs. Great Mazinger.