A film series in the long-running Ultra Series, consisting of two movies, Ultraman Zearth, and Ultraman Zearth 2: Superhuman War: Light and Shadow.
The movies were released in 1996 and 1997, respectively.
Both movies serve as a parody/spoof of the Ultra Series, in general. It also features product placement from the Idemitsu petrolum company, in which the character of Ultraman Zearth is created to advertise for.
This tag implicates ultra_series (learn more).