[1] Alcazar's first credited U.S. work appears in four publications cover-dated December 1973: penciling and inking the six-page stories "Suicide ...Maybe" and "A Thousand Pounds of Clay" in the Archie/Red Circle comic book Chilling Adventures in Sorcery #4; penciling the two-page story "The Old School" in Warren Publishing's black-and-white horror-comics magazine Creepy #58; and inking penciler Rich Buckler's cover of Marvel Comics' black-and-white horror-comics magazine Vault of Evil #8.

[5] Alcazar quickly became a regular freelancer for Archie, Marvel, Warren, and soon DC Comics and Charlton Comics, primarily drawing horror stories but also sword-and-sorcery (drawing the cover and inking penciler Val Mayerik's "Thongor!

Writer Shaqui Le Vesconte said of Alcazar's Space: 1999, "His style was very Gothic and experimental, using a variety of techniques that could be described as 'monochrome psychedelic', and matching the nightmarish feel of episodes like 'Missing Link', 'End Of Eternity' and 'Dragon's Domain'".

He wrote and drew the eight-page story "Paradise" in the comics-anthology magazine Heavy Metal vol.

[3] In 2011, he began penciling, inking, and digital coloring the Vices Press series M3,[7] which won the 2012 award for Best Comic Book at the Burbank International Film Festival.