5000 years ago, the Kaiju Eugenicists, with Gauma being one of them, brought fortune to a certain country through the use of their power to control Kaiju. They were known as "dragon controllers" to the neighboring country. Juuga used to look up to Gauma as well. The princess of their country became interested in the power, but then the Kaiju Eugenicists were betrayed by the country, while also betraying the country themselves. Gauma, having shifted his loyalty to the princess over his comrades, killed them and then fell over, and seemingly died, gaining the scars on his face in the process.
5000 years later, Gauma and the Kaiju Eugenicists were revived in the modern day. They now consider Gauma to be a traitor for piloting Dynazenon to fight against their Kaiju.
The Kaiju Eugenicists were behind the attacks of Shalbandes and Greyjhom before they revealed their presence to the Dynazenon pilots, and branded Gauma a traitor. For the most part, Mujina simply tagged along while her other teammates did their work. She was allowed to control the Kaiju Didoras when she got the chance, but didn't do well in battle.
Mujina met with Koyomi Yamanaka at a Seven 21 shop. While they were conversing as he was drunk, she said to him that they were quite alike as they both didn't know what they truly wanted. Having forgotten his umbrella back at the restaurant, Mujina took the chance to give Koyomi her umbrella while stealing Dynastriker in the process while he was too drunk to notice. In a warehouse, the Kaiju Eugenicists almost get into an argument over what to do with it, and Mujina wasn't sure. Gauma used Dynadiver to track down Dynastriker, encountering the Kaiju Eugenicists. They fight and get Dynastriker back, and Gauma attempted to kill them only for the warehouse to come crashing down on them. Mujina later helped Onija control Bullbind after being encouraged by Sizumu and Juuga, and fought against Dynazenon.
After Garnix's defeat, Mujina left the team to find something to do with her life. Mujina and the other three Kaiju Eugenicists attempt to use Instance Domination on Gagula, but realize Sizumu is inside. They allow themselves to be devoured by Gagula for it to power up into its second form. However, they still lose to Gridknight and Dynarex. The Kaiju Eugenicists are destroyed along with Gagula.
- Instance Domination (インスタンス・ドミネーション Insutansu Dominēshon): An ability that puts a Kaiju under her control, and makes it grow to giant size.