30th Gundam Perfect Mission is a short original video animation (OVA) officially released by Sunrise in celebration of the 30th anniversary of the Gundam metaseries. It features all the titular and mascot gundams of the main series in a non-cannon conjoint mission. (Source: Gundam Wikia)

The series follows Arashi and his Wild Liger. The main antagonists are the Death Metal Empire, lead by Gallagher. They use Zoids for conquest, and have at their command many Zoids and warriors, including the Four Heavenly Kings. Arashi longs to follow his father's footsteps become a Zoid Hunter, and find his ultimate Partner. At the beginning of his journey, he partners up with the Wild Liger and meets Bacon and Team Supreme, who tell him about the Great Ancient Treasure Z. (Source: Zoids Wiki)

Around the the 37th year of the Meiji Era (1904), in the midst of the Russo-Japanese war, the small Japanese army, in need of assistance, uses its special flying (thanks to a benevolent demon) ship, the Amanohara, to attack Russia's major base at Port Arthur (Lushun). Umakai Shintaro, a Russian diplomat originally from Japan, defects and goes to Sapporo to teach at a girls academy. However, that girls academy is not typical—it is on board the Amanohara, and the five girls Shintaro teaches are known as the Raimu Unit—girls with the ability to summon powerful beings to fight for them. Shintaro eventually becomes their teacher and general in battle, and so the six embark on a weird and excessively erotic journey, as Shintaro helps the girls overcome their weaknesses, become stronger for the final stand at Lushun, and also understand the motives of the Russian Spiritual Corps that assist the opponent, which, unfortunately, has one member whom Shintaro knew well... (Source: ANN)