The Grateful Dead might've brought rock's longest, strangest trip to an end on July 5 in Chicago, but the Core 4 of the final iteration of the Dead are far from finished with music.

The Grateful Dead’s Bob Weir and Mickey Hart are the latest additions to the lineup at the Lockn’ Music Festival. Weir will perform as the Featured Guest Of The Day appearing in unique artist collaborations on Saturday, Sept. 12. Hart will curate a “deep rhythm experience” at Lockn’s forest stage during two consecutive one-­of-a-kind late night presentations, tuning The Woods with sound, lights, and vibrations and performing a third evening on the main stage with EOTO.

Additionally, the Dead's Phil Lesh will hit the stage with another rock icon: Carlos Santana.

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"It is an honor to be invited to share the stage at Lockn’ Festival with my musical brothers and sister, Phil Lesh, Warren Haynes, Phil's Band as well as my talented wife, Cindy Blackman Santana," Santana tells Billboard. "Each bring their own unique vision and touch that will make for a rainbow explosion of sound, resonance, vibration that will touch everyone at the center of their heart. I know my brother, Jerry Garcia, will be smiling down on us as we compliment and soar into the heavens to create a new landscape of light & love, where time, space and gravity disappears and it is just the music and your heart."

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Elsewhere at Lockn' Fest, Dead vets Mickey Hart and Bill Kreutzmann will perform (separately), meaning anyone who hits up the Sept. 10-13 fest has the opportunity to check out the Core 4 (though not together) during their post-Dead period.

Lockn' 2015 will also feature a celebration of the late Joe Cocker and a concert commemorating 50 years of Jefferson Airplane. Check out the lineup above and get tickets here.