The oath Moomintroll and Sniff make in Comet in Moominland: "May the ground swallow me up, may old hags rattle my dry bones, and may I never more eat ice cream if I don't guard this secret with my life."
The Hemulen acting as Tingumy and Bob's translator in ''Finn Family Moomintroll," especially since he keeps missing a few points and telling Sniff that they're insulting him.
In the first storyline of the comic strip, Moomintroll briefly dresses up as a soothsayer, upon which a ghost appears, thinking he's dressed up as a ghost and getting angry at him for "haunting without a lisence."
In one episode, Sniff gets rewarded for helping fix a roof with pie. He then goes around pestering to help people in hopes of getting food as a reward. He winds up runing Snufkin's tent and letting Little My babysit the Fillyjonk children because Fillyjonk has gross cooking. All sorts of wacky hijinks ensue.
In another episode Moominpapa makes a sculpture of his hat, hovewer not a single person asked for their opinion about it saw it as a hat (Sniff and Hemulen saw it as a cake), making Moominpapa quite angry.
1969 Live-Action Series
In one episode, the Moomin family show the King the Moominvalley prison, and the prison is just one bizarre instance of Insane Troll Logic after one another:
The cells are all equipped with shovels and crowbars, because there's no reason why being in jail should stop the poor criminals from practicing their chosen professions.
It's explained that all the criminals are in jail only for as long as it takes them to dig themselves out — "one has to work for one's freedom." Petty criminals are placed in cells with a soft earth floor that's easy to dig through.
The jail is equipped with an electric chair... which turns out to be a chair with an electric light attatched, so that the police chief can sit in it and read his crime novels in the evening.
In one cell, the Moomins' still is located. Since stills are illegal, it's kept in jail — though in an open cell, because it can't run away anyway (and this way Moominpappa can make moonshine under the watchful eye of the police chief).
The theatrical play the Moomin family put up in the last episode (heavily inspired by the one they put up in Moominsummer Madness) quickly becomes So Bad, It's Good. The plot makes no sense (mostly revolving around an old woman plotting to have a lion eat her cousin so she can inherit said cousin's porcelain), the lines swap between being in rhyme and not, stage directions go wrong, the actors keep missing their cues and fumbling their lines or going off to make coffee when they're supposed to be on stage — except for Misabel, who Chews The Scenery to a ridiculous degree and at one point begins doing Moomintroll's lines when he forgets them, playing both sides in the conversation.