[9] In human forms, they operated in Space Radio Wave Research Institute (宇宙電波研究所, Uchū Denpa Kenkyūjo) led by a director.
After reviving Bemstar and Seagorath as test subjects, the Nackles stole Saturn Z bomb from MAT and murdered the older Sakato siblings, Ken and Aki, to diminish Go's spirit.
[10][11] Once Jack was killed and put to crucifixion on their home world, the Nackles disable MAT's aircraft and brainwashed them (saved for Yuriko) in their failed attempt to bust into the Research Institute.
This particular Alien Bat held Jirō and Rumiko as his hostage while using a revived Zetton in his campaign against Ultraman Jack and stripping MAT of their assets while they were busy fighting his monster.
The Inter-Galactic Defense Force (including the Ultra Brothers members and a rookie Mebius) managed to counter the invasion but the battle ended with huge losses on both sides.