Sad news to report this afternoon: Rumpus, the Harlequin Great Dane best known for his role in Lady Gaga's iconic "Poker Face" video, died earlier this month after taking a hike (an actual one, not the metaphoric kind) in his hometown of Los Angeles. He was just five years old.

According to TMZ, Rumpus' death was unexpected. His owner, Suzzane Kelleher-Duckett, told the Web site that the award-winning show dog appeared to be in good health, and showed no signs of injury after taking a lengthy hike. As such, an autopsy was performed on his body and results are expected soon.

Rumpus appeared poolside (along with his mother, Lava) in Gaga's Video Music Award-nominated "Poker Face" video, and also made cameos in her "Love Game," "Paparazzi" and "Eh Eh (Nothing Else I Can Say)" clips, too. TMZ reported that he was also scheduled to appear in Gaga's upcoming "Bad Romance" video, but that role will now go to Lava instead.

According to the Web site run by Rumpus' breeder, Pacific Coast Harlequins, he enjoyed "hiking and trail riding … hit[ting] the trails 2-6 miles every day, rain or shine," and had recently filmed a commercial for Cesar dog food. He had also just sired a litter of six puppies with a fellow champion Dane named Gracie.

Those who worked with Rumpus recalled a star-crossed dog whose unbridled energy and free spirit made him a much sought-after talent. But those same eccentricities also came with a price. Just last month, "Poker Face" director Ray Kay told MTV News that he and Rumpus had a volatile relationship during their shoot, one that threatened to shut down the production entirely. But that, when the dog was on, there was no one better to work with. Or, you know, something like that.

"Never work with animals or children, that's the age-old Hollywood rule, and it's true. Things just don't go according to plan when you work with them, and that was true in our situation here. Those dogs just wouldn't sit still, and they wouldn't do what we wanted them to do," Kay told MTV News. "So there were two dog trainers on each side of the shot, trying to hold the dogs down in the position they were supposed to be in, but they just kept getting up, or like looking in the wrong direction … so, actually, we never got the shot in-camera the way it's shown in the video. We had to combine different takes of the dogs to get the shot the way it was in the video. "

By Cara Alwill

Bob Bryar, the drummer for My Chemical Romance, has filed charges against Daniel Schaffer, the self-proclaimed "dog trainer to the stars" after the death of his German shepherd mix, Dixie. The trainer has given conflicting explanations for the death.

According to People, Bryar brought his pooch to Schaffer's kennel for intense training to help him recover from abuse and emotional trauma caused by his former owner. Bryar spent $7,500 on the training in April, but when he called to check in on the dog, the trainer reported that Dixie was killed when a drunk driver struck the vehicle in which Schaffer was carrying several dogs, according to the court papers filed in Burbank Supreme Court. Bryar then received a call that evening stating that the dog had died from a different cause.

"Schaffer called (Bryar) again and informed him that he could not say goodbye to Dixie for she had been 'cremated due to her condition,'" the lawsuit says. Two days later, the trainer "delivered an urn allegedly containing Dixie's remains." After Schaffer could not produce a police report documenting the car accident, he changed his story and said the dog died in her sleep, and later changed that story to say she died under other circumstances.

"I don't even know what happened to my best friend and miss her more than anything in the world," Bryar said. "The devastation I feel is beyond words."