Doug later replaced the Helcat, and joined Mach Storm in fighting Alpha. Dr. Pierce A scientist who works in Blue City, Dr. Wolfgang Pierce is the leading expert in Zoid technology and Fuzors. He provides assistance to the Mach Storm team on several occasions. Dr Pierce is secretly working for Alpha, developing new Zoids for him. He created the Energy Liger and Gorilla Tron (Ray Kong in the Japanese version) as the "ultimate Zoids". However, Alpha discarded them in favor of the Seismosaurus. Embittered, Pierce used the Zoids to undermine Alpha's plans. Eventually he used them against RD and nearly beat him, but Blake interfered with battle allowing RD to win. Pierce survived but was depressed that his Energy Ray Liger could lose. Haldo A longtime friend of Helmut's and a former member of the Mach Storm team, Haldo is now a transport pilot who hauls goods in his Gustav. He still supports the team by offering them work, and has helped them out on several occasions. He provided Sigma with his Leostriker, and later helped smuggle the team out of the city after being imprisoned by Alpha. He has piloted several Gustavs in his lifetime and has the control stick of each of them in a display case. Jean A skilled acrobat in a circus, Jean was, in fact, a professional Zoid thief working with a gang in Blue City. He tried to woo Ciao, which did not help him out when she discovered his true nature. He and his team were taken out by the PKB, with Ciao personally disabling his modified Arosaurer. Keith A former Zi-Fighter and Amy's former lover, Keith (Kidd in the Japanese version) was soundly beaten in a championship battle and left the league. He returned with a Holotech Sabre Tiger, an unusual Zoid that had the ability to turn invisible and conceal itself from sensory detection. Using the Zoid, he went on a rampage, attacking other Zi-Fighters. He was able to destroy many Zoids including two Blade Ligers, the Dark Assassins' Killer Spiner, and Sigma's Boldguard before being stopped by the Mach Storm team. Marvis A former member of the Mach Storm Team, Marvis used to be Helmut's best friend and Sigma's mentor. However, he had a falling out with the team, which caused him to go on a rampage; killing a member of the PKB. He was hunted down and captured by