The episode "Day at the Park" had Yakumo, and the other (minus Mushra) invited to a festival, while Mushra gets little revenge for being sent away by Yakumo. Mostly it amounts to him helping some other enterrans (who are frightened of humans) set up some "booby-traps". Then he sits back and watches as Yakumo and the others have to deal with the now (relatively) harmless traps.
Honestly, I think that guy was having just a little to much fun at their expence.
The three kittens Sanju, Rei, and Sen are not only cute, they're good Plucky Comic Relief during season two. All the while manageing to avoid the Scrappy department.
Mushrambo of all people gets a really good dig in on Gyasa in "Mushrambo: The Ultimate Samurai".