The savoury snacks giant is also replacing Spicy flavour with an improved version of old favourite Roast Beef.
Available early next month for 12 weeks, Mystery Tongue, which is pickled onion flavoured, can turn tongues either blue or green thanks to a safe food dye. It follows last year's turns your tongue blue' version, but this time munchers must stick out their tongue to discover what colour it has turned.
Trade marketing manager Cath Painter said the company receives more than 40 requests a month to bring back the Roast Beef variant.
Both arrivals will be supported by ads in children's magazines Smash Hits, Dandy and the Beano and on Cartoon Network, as well as instore PoS.