Odd Jobs, Katsura, and Sakamoto disguise themselves as Renho to join Fumiko in infiltrating the enemy base.  Dark Vader, feared by all as the evil lord, plans to use the Renho's anti-samurai Gunsams to attack while the people of Earth are distracted by the rain.  Gintoki and the others must stop the invasion of Earth before it's too late, but instead they appear to be bonding with the Renho.  That is when Elizabeth, General Eren, appears!
That is what I learned 
from my friend on Earth.
Eso es lo que aprendí de mi amigo en la Tierra.
Foi isso o que meu amigo 
na Terra me ensinou