已故

已 = ㇖ + 一 + 乚 : Kinda looks like a dredger. Maud Younger wants to dig a tunnel from the space station to earth, so she already used a dredger to dig up the walls just inside the space station. Unfortunately there are a lot of flutes built into the wall, and the dredger is of no use here, so she had to stop. Instead she then has to use a shovel and a sickle to scratch the flutes free and lever them out afterwards.

故 = 古 + 攵 : Mnemonic symbol: This character only appears in 做, so we don't need a strong mnemonic symbol. We should be able to refer to 故 when we think of 故事 or 故意. Because it fits nicely to its components, I'll think of it as in the meaning of 故墓, an old grave.

故 = 古 + 攵 : There is an ancient cloister in the space station's bathroom, and Gitta Giraffe once heard a story from her fellow astronauts that there's an old tomb inside with lots of treasure. One day she can't hold herself back anymore and deliberately breaks the cloister open using a sledgehammer.