What discounts do Merlin Pass holders get inside the attraction? As a Merlin Pass holder you'll get 20% off in our retail shop and our canteen. Related articles Do Merlin Pass holders get free entry or a discount on Bear Grylls Adventure tickets? Do I need to bring my Merlin Pass with me? Do I need to know how to swim to take part in snorkel? Are sharks or any other sea creatures and fish within the tank dangerous? Do I need to book in advance?