Nipponia is a distant, tiny and isolated planet, named by it's inhabitants so. Originally an exploration craft, the ship malfunctioned and crash landed here. The crew's only contact with Earth was the several Japanese anime channels... This inspired the otherwise very crafty minifigs to salvage and rebuild their ship into various weaponries to defend their new home.
Nipponians are few in numbers, so they rely instead on their Warrior Guardian Giant Lords (戦士の保護者巨人の主 (yeah i translated them)).
Warriors are led by Armored Heavys (装甲重い) Who have shoulder-mounted LR gun, and sawblade. Regular warriors have a gun and tool (all Nipponians can repair vehicles).
Those who were severely wounded in the crash were converted into CyberRobots (Cyberのロボット).
Probably the strongest infantry unit, behold: The Schoolgirl with Orange Transparent Chainsaw!
As heavy support, they also made a hardsuit, the Gun Max(最高銃)
/Also, there's a sniper (狙撃兵)with ridicolously large rifle, but i failed to take a picture. Yeah, I suck./
But the main attractions are the Warrior Guardian Giant Lords (戦士の保護者巨人の主), who are all Ganmen from the Tengen Toppa Gurren Lagann anime (yeah, i'm kinda a fan of that.):
The Dayakkaiser, Long-Range artillery
The King Kittan, close-combat master
And The Gurren-Lagann, who leads Nipponians to Victory!
Final shot of the victorious warbrigade (勝利戦争の組)
They're nothing serious, just hastily made fun fighting force in scifi setting.