Over those three decades, the music never stopped until Jerry Garcia, the band's lead guitarist and composer of hits such as "Truckin'" and "Casey Jones," died of a heart attack in 1995. While members of the band continue to be active, Garcia's death meant the end of the Dead for many of its followers.

But now, for Deadheads in the doldrums, there's a way to recapture the magic online in a videogame, "Grateful Dead Game: The Epic Tour," that goes live on April 20.

"What we're doing is creating an adventure by traveling through Grateful Dead history, Grateful Dead time and space to make their way back to ten shows," said Adam Blumenthal of digital media company Curious Sense, which created the game.

Since Rhino Records took over recording and merchandising for the Dead in 2006, they have tried to take the band's music to an audience - particularly younger listeners - that goes beyond the nomadic artists, artisans and party people known as Deadheads who scheduled their lives around the band's tours.

There are a wide range of products including skateboards and lunchboxes bearing the Dead logo, and according to Rolling Stone magazine, a new movie about the band is in the works.

For the game, fans were asked to select their favorite concerts, and the makers gradually whittled the list down to 10 unforgettable shows from 1970-1990.

Players move from venue to venue, joining forces to shine the Dead's "love light" in dark places. The "light" represents the collective "positive vibe" of the Dead, and it becomes a beacon as players show acts of kindness, cooperation and cultivation of flower gardens.

"There's not really an end to the game," said Blumenthal, which seems appropriate for the jam band. "It's a game where the objective is to keep having fun rather than get to the end."

Groovy.

"Epic Tour" has none of the drug use or talk normally associated with the band and its followers.

"There's nothing explicit," said Blumenthal, who was bound to keep the game family friendly. "The visuals are psychedelic, they're fantastical, they're colorful, they're whimsical but no drug references."

While a younger audience may sound out of reach for a hippy band from the 1960s, Blumenthal said the average Deadhead is 40 years-old, and a 2011 study conducted by ESA (Entertainment Software Association) puts the average age of a gamer at 37.

"Online gaming is now a mass medium, played by as many adults as kids," said Blumenthal. "We create a new way to experience music through immersive gaming - re-packaging the album as a game."

Other musical acts are beginning to test the videogame market too, including a recently announced one from hip-hop mogul Jay-Z and a Jimmy Buffet ‘Margaritaville' game.

As for the "Epic Tour," the top concert chosen was one played in 1977 at Cornell University. "There is a rabbinic-like debate about the best show," laughed Blumenthal who believes the band was at its peak in the late 1970s.

"A grand Ivy League campus in upstate New York, gorgeous waterfalls and gorges. It was a spring day, May 8, 1977," recounted Blumenthal. "And when people came out of the show that night there was a blizzard! All these things add up to epic."

(Reporting by Jordan Riefe; Editing by Bob Tourtellotte)

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