The popular brewpub/hotel chain will offer plenty of festivities open to all ages, including trick-and-treating and live music at its Kennedy School and Grand Lodge locations. To celebrate the rare blue moon, the Blue Moon Tavern and Grill will have a special Blue Moon cocktail: a purple lemon drop made with Spar Vodka and Thai butterfly tea, served in a keepsake blue Silipint cup. There will also be food and drink specials at the Blue Moon and the Kennedy School. Guests who show up at any location will get a "just for fun" stamp for their McMenamins passport, and those who show up in costume at the Blue Moon will also receive 10% off their bill.