This seemingly ridiculous ability has been a dungeon buster so far in our group. I may be off in a few points here but let me see if I understand this incredible ability...
Fey touches boss monster; boss monster cannot attack because he has to laugh for a full round without a savings throw, regardless of boss monster's toughness (look out Zeus... you are gonna giggle for a round); party completely and utterly rapes boss monster
At least that is how it has played out so far with our group. Seems broken to me. Hope we are mistaken with this "ability", please advise.