UPDATE 09/11/19: October 20th has also sold out, leaving October 29th as the only party date with tickets available.
With a week to go before the debut of the new Oogie Boogie Bash-A Disney Halloween Party at Disney California Adventure, the entire 20 night event is almost sold out. Oogie Boogie Bash, a separately ticketed after-hours event that has replaced Mickey's Halloween Party, begins September 17th. Currently, tickets remain for just TWO nights: October 20th and October 29th. All other nights are sold out. The event features trick-or-treat stations, a Descendants-themed dance party, a Villains Grove trail, the Frightfully Fun Parade, and Mickey's Trick and Treat, plus Villainous!, a new World of Color show.