Rimuru decides to throw a summer festival resembling the ones held in Japan. The monsters have never experienced a summer festival, but when they hear that it's a party, they go all-in to prepare. All the monsters of Tempest work together and eventually come up with masks, paper lanterns, and even festival floats. On the day of the festival, everyone in the town enjoys piping hot takoyaki, cold shaved ice, yukata, and a Bon dance. In the end, they fill the skies with fireworks as the festival reaches its climax...
preparations began to show off 
the best that monsters can do.
بدأت التّحضيرات بإظهار أفضل
ما تستطيع الوحوش فعله
haben sich meine Dämonen
richtig ins Zeug gelegt.
les monstres se consacrèrent
aux préparatifs.
sono cominciati i preparativi 
con il massimo impegno delle bestie magiche.
os preparativos que mostram o melhor
que os monstros podem fazer.
магвери и начали 
работать до седьмого пота.