Robin explains why the ritual is so important to him.
The Moonah Ston Ritual is an ancient ritual celebrating the moon. Robin is passionate about it. In the episode "Moonah Ston", the ghosts perform the ritual during a lunar eclipse.
The Ritual[]
The ritual involves all the ghosts meeting in the dining room (the centre of the former sacred site). One of the ghosts (usually Thomas , though the Captain wins the vote in the episode) does a reading base on the original text. The original ritual is roughly "Thank be to moonah. Good light in sky", and the Captain paraphrases it as "Thanks be to the wondrous moon, and the guiding light it giveth between 2100 hours-" (the rest is unintelligible due to the loud chanting).
The ritual also involves most of the ghosts dancing around the middle of the dining room and chanting "moonah stonah". Robin also howls at the moon from the middle of the room.
After a while, Alison banishes the ghosts and distracts them with a DVD of Friends.