Hell Fighter 17

Hell Fighter 17 is a replica of Android 17 constructed in Hell by the combined efforts of Dr. Gero and Dr. Myuu, who sought to create the ultimate android. Unlike the real Android 17, Hell Fighter 17 is completely obedient to his creators' commands. He phases through the barrier between Hell and the living world to merge with the real Android 17, forming Super Android 17 — one of the most powerful antagonists in Dragon Ball GT.