I’m not sure there’s much of a point in watching anime now that this series is over. Consider that the last episode of this series features:
A little stumpy robot head with arms and legs:
Fused to a bigger robot:
Which is piloting a larger version of itself, formed from a space battleship:
Which it itself the power core of an even larger version of itself, formed from a space battleship the size of the moon:
Which is itself the core of a robot two light years high.
The robot is powered by the will of all mankind.
It is fighting the enemy of not just mankind, but of every living thing in the universe.
In episode 21 or thereabouts, the third iteration of the giant robot punches a battleship of the enemy fleet so hard that it flies into another universe.
In the final battle, the giant robot and the leader of the enemy race, which has also taken the form of a giant robot two light years high, are fighting in a pocket universe. They fight by picking up miniature galaxies and throwing them at each other like ninja stars.
Where do you go from there.