As per information from http://otakingdom.blogspot.com/ , you can enter the park for free provided that you're pre - registered online or at the Group Sales Office near park gate, and ofcourse by wearing an “otaku” costume of a character from Animation, Comics, Toys, Gaming, TV, or Movie
reference:
http://otakingdom.blogspot.com/
www.enchantedkingdom.com.ph