Slaughterhouse and a surprise performance by Eminem helped make the 30th anniversary of Casio’s G-Shock celebration at New York City’s Manhattan Center last night (August 9) an affair to remember for the ages.

With Em being no stranger to G-Shock—wearing the watch frequently, including in the music video for “I Need a Doctor,” and at the 2010 MTV Movie Awards—it was fitting for Slim Shady to salute Casio for three decades of the stylish digital watch.

But before Em could take the stage and throw the capacity NYC crowd into a frenzy, his Shady Records’ group, Slaughterhouse warmed fans up with new material off their upcoming album, Welcome to: Our House, which drops on August 28. Together, Slaughterhouse members Crooked I, Joell Ortiz, Royce da 5'9" and Joe Budden performed the group’s singles, “My Life” and “Throw It Away.”

During their set as the opening act, Budden paused to ask the crowd if he could “take them back a few years.” The New Jersey representative took them back nine years to be exact, raising the energy in the popular venue with a performance of his 2003 banger, “Pump It Up.”

It wasn’t long after the conclusion of Slaughterhouse’s set, that Eminem made his arrival onstage. Rocking a hoody, which was later shed for a white sleeveless tee, and cargo shorts, Em opened up with “Won’t Back Down,” sending the crowd into a high fever with his mere appearance, which was rumored in the days leading up to the show.

With a live band setting the mood and clips from some of his iconic music videos playing on the big screen behind him, Em had the crowd in the palm of his hand and he proceeded to give them what they wanted.

The masterful Detroit rhyme slinger ripped into classics such as “My name Is,” “The Real Slim Shady,” “Cleaning Out My Closet” and “Love the Way You Lie,” dedicating the “Lie” to the ladies in the audience.

Taking another moment to reflect and then dedicate, Em performed his stadium-music hit, “Not Afraid,” stating that it was his fans who helped him get out of a dark place, while also encouraging everyone who has faced personal struggle or who still struggles to sing along. After “Not Afraid,” Em left the stage to a hero’s salute from the crowd, but like a true MC—with a ton of hits in his extensive catalog—returned to the stage for an encore, with “Lose Yourself,” the hit single off his 8 Mile movie soundtrack in 2002.

Besides the fans and media in attendance, Busta Rhymes, Ice T and wife Coco came out to show their support and enjoy Em’s performance.

Definitely a night to remember!—Kadeem Lundy