Korvo finds legitimate success as a magician, using his sci-fi tech combined with sleight of hand. He then throws it all away in a complex Batman Gambit because he realizes that he pushed his family away.
All of the family mourning Korvo when they think that he died, complete with arranging a funeral for him. That Korvo reveals how he did it and then sits them down for ship repair lessons doesn't make it any less sad.
Yumyulack is horrified to learn that the "magicians" he killed when they threatened Terry were actually paid actors.
In the B plot of the wall, it's revealed that Pedro goes on a dangerous bartering quest to get the insulin his father needs. It turns out that when the only food you're given is candy, then your life is forfeit as a diabetic. Pedro dies thanks to the Duke, but gets the insulin; his father starts asking if "small people" get into heaven.
Terry and Korvo Steal a Bear
Molly the mouse accepting her fate so her owner could survive, she even kisses the glass reassuringly before dying peacefully in front of her crying owner.
Cherie's death at the hands of Tim after he betrays her so take over the Wall and keep the existence of secret passage to the outside world a secret.
Retrace-Your-Step-Alizer
Shlorp is revealed to be a "strict, totalitarian utopia". It is implied the reason why Terry loves Earth so much is due to the freedom he is allowed: on Shlorp, he is signaled out for not buttoning his robe all the way, because "conformity is cool".
Season 2
Halk feeling guilt over not being able to save everyone from a Nerd avalanche and having nightmares to digging up their corpses.
Declan was another victim of Yumyulack who was sent to the wall. He was greeted by Mia the Wall Greeter who tells him that he can live his dreams to design clothes. He is initially satisfied but is gruesomely killed by Ethan before he can even go to the clothing shop.
Tim discovers that Ethan has been committing murders, which genuinely saddens and disturbs him.
Tim: I didn't know he was killing people...
Cherie survived Tim stabbing her and tossing her out of the secret exit. She looks worse for the wear.
Season 3
"Hululand" has Tim and Cherie put an end to the wall, the citizens are restored to full size and the Solar Opposites are shrunk and trapped within the very prison they created. Only to reveal that this is all Tim's Dying Dream before he succumbs to lead poisoning via a Burger King Star Wars glass he had been drinking from. In the end he is given a Viking Funeral.
Stephen has gone insane from despair over the loss of Molly and plans to use his mosquito army to restore balance to The Wall by killing off half the population. His seeming death is almost a mercy that this point.
Halk sacrifices himself to kill the Queen Mosquito.
"The Wall" subplot ends this season with Cherie forcefully separated from her baby Pezlie by the nuns as they proclaim her a "child of the wall" and brand her on the forehead, marking her as a religious icon.
"The Fog of the Pupa" caps off the third season as the Solar Opposites are truly forced into the lives of average earthlings. Getting actual jobs (the case Korvo and Terry) and honestly applying themselves in school (Yumyulack and Jesse) all so the Pupa can have some sort of structure in his life. Everyone clearly hates it, they're absolutely miserable. They only go through with it at all for the Pupa's happiness.
