[FairyKing]

Quote:

Originally Posted by Starman

Green as the lead, red, blue, orange, black.

With violet & gold as sixth rangers.

"Wind power, Eco Green!
Thermal power, Eco Red!
Water power, Eco Blue!
Solar power, Eco Orange!
Bio power, Eco Black!
Chikara Sentai! Ecoger, let's go!" ("Ecoger, ikou!" for the pun)
"Nuclear power, Eco Gold! Clear to go!"
"Fossil power, Eco Killer! Going hunting!"

Chikara Sentai Ecoger means "Power Team Eco(logical)-ger" and the theme if it wasn't obvious is energy sources: Wind, geothermal, water, solar, biofuel, nuclear and fossil fuels. Protecting the environment is obviously a major message of the story.

The villains are the Dead Planet Army Kaosen (phonetic spelling of "chaos" + osen meaning "pollution"), invaders from another world trying to pollute the Earth to make it a more suitable home for their overlord, with monsters themed after various pollutants and other environmental hazards, or just common litter for their footsoldiers. To fight back, the spirit of the Earth herself chose five young adults with great potential - a proud soldier (first Red), a stern rescue pilot (Green), a flirty marine biologist (Blue), a cheerful astronaut cadet (Orange), and a semi-feral forest ranger (Black) - and bestowed them with the powers of clean energy, in the form of ranger suits, weapons and mecha, naturally.

Eco Gold is the normal sixth ranger, a brilliant scientist and friend of Orange who learned about the Ecoger's battle and supported them. After studying their powers enough, he developed his own ranger arsenal to fight alongside them. However, his nuclear power is dangerous if he loses control, and Earth refused to recognize him as the sixth Ecoger until he proved he could handle the responsibility. His aesthetic is more technological than the others.

Eco Killer is an evil ranger, the first Red after betraying the rest of the team when Kaosen promises him wealth and status in their polluted world. This is not a spoiler, the promise would be revealed to the audience in the second episode, though he'd keep up the ruse of working with the team for a while and even become their leader.
In the battle where he reveals his betrayal, a fire breaks out and a hotshot firefighter rushes to the scene and manages to seize the thermal powers from him. She becomes the second Eco Red, and Eco Green steps into the role of leader. This leaves the first Red de-powered for a time, until the Kaosen overlord personally grants him new power as Eco Killer. His aesthetic has a dinosaur bone motif and his shade of purple evokes oil.

My first thought for their mecha was vehicles powered by clean energy but now I'm thinking they could be more like elementals, changing into their giant forms similar to Magiranger. Green as a wind bird, Red as a magma golem, Blue as a water serpent, Orange as a sunlight wisp, Black as a tree ent, and Killer as an undead T-rex! Gold is the only one with a traditional mecha, a nuclear submarine. The five core members combine to form Eco Gaia, while Gold's submarine and Killer's T-rex both turn into robos on their own.