Tear Jerker / Commander Kitty

• Ace's Heroic BSoD. After Mittens' transformation from Bumbling Sidekick to Hypercompetent Sidekick, Ace begins doubting himself as a leader and falls into depression, and later seems to have given up completely. He gets better, but his despair over having been apparently replaced by a younger, smarter spacer is surprisingly tragic.
• And when Ace does get better, poor Mittens ends up taking the brunt of him and becomes his old spineless self. While Ace treating him like dirt is at least a little justified, you feel pity for him being stuck as the team's No-Respect Guy once again...
• After getting her real arm back, surviving Zenith's assault, and seemingly falling for CK, Nin Wah is revealed to be an android clone and shuts down like all the other robots when Fortiscue deactivates the Zenith Project. Sure, we have the real Nin Wah back right after that, but her clone had become a character herself by this point, and the way she shuts down doesn't look particularly pleasant...
• And later, Android Nin Wah gets laughed at by the original for remembering her history wrong (or did she??), when just earlier it was revealed that clones actually have their minds messed with by nanomachines. The last we see of her for a while is her head just sitting on the shelf, seemingly resigned to her fate.
• Zenith's current state. Whether ranting about conquering the galaxy or just happy to help, she was always an expressive, entertaining character. Seeing her reduced to just a braindead calculator staring blankly with her ears and tail set aside in a box like any other spare part is a little heartbreaking, especially since she'd made Nin Wah a sweet new cyborg arm and outfit right before Nin Wah herself inadvertently gave her a catastrophic system crash.

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