Rob Martinez, also known as Vulkan The Krusader, is an American recording artist, record producer, songwriter, director, musician, and designer, born and raised in Managua, Nicaragua. He has also lived in Brooklyn, Los Angeles, and Miami.

Vulkan is a genre-bending hip-hop/R&B artist, and also often combines all these sounds, to create something new and cinematic, in his approach to music.

He has been active, since 2011, and is often inspired by medieval lore and anime. Vulkan is a prolific songwriter, and is also best known for most notably working with A$AP Rocky.