Marvin Jones III, also known as Krondon, is an American rapper and actor from Los Angeles, California. He is a member of the group Strong Arm Steady, along with rappers Phil Da Agony and Mitchy Slick. As an actor Jones portrays the character Tobias Whale in The CW superhero television series Black Lightning, and voices Tombstone in the superhero film Spider-Man: Into the Spider-Verse.

Strong Arm Steady, often referred to as SAS, is a hip hop group in California's underground hip hop scene. As of December 2009, the act consists of members Phil Da Agony, Krondon, of Los Angeles, and Mitchy Slick of San Diego, California. Originally an amorphous collective of at least eight, formed as an alternative to the gang-focused productions of West Coast rap's then-dominant Death Row Records, SAS pared down to four members for recording in the studio and performing live, with Xzibit as the frontman. Since he left the group in 2006, the three remaining members have been a stable trio.