Passers-by were encouraged to visit the brand experience by 'joy agents' dressed in purple. Visitors were given a scratch card to reveal, where those who were unlucky left with a bar of Cadbury chocolate, while those successful participants were invited to visit Freddie Flintoff in the Joynormous machine.
The former cricketer was dressed as a genie and asked the winners questions about their personality to determine the best prizes to give. One consumer received a gift worth £10,000.
Bombrini added: "The challenge with this activation was not to define a prize, but to tailor-make each prize to what [the winners] love. We couldn't plan everything in advance – we were doing everything in the moment."
Agencies Golin and Initials collaborated to deliver the experience.
Cadbury's on-pack promotion is offering 20,000 personalised surprises to fans of its Wispa, Starbar, Crunchie, Dairy Milk, Boost and Twirl varieties.
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