'Wolff' by Maroto was published in the UK by New English Library in the magazine Dracula. Dracula was published in the US by the Warren Publishing Company under the title Dracula Book 1 in 1972; the cover was by Esteban Maroto.
In the 1970s he started to be known in his own country when the magazine Trinca published Alma de Dragón. He designed the "metal bikini" for the character Red Sonja, in Savage Tales #3, Comixscene #5, and in the first issue of The Savage Sword of Conan and pencilled her first solo story, which was inked by Neal Adams and Ernie Chan. He also redesigned Satana for Marvel Comics and drew her second solo story in Vampire Tales #3. In issue 4 of the same series he drew an outstanding adaptation of the short story "The Drifting Snow" by August Derleth.
Maroto joined Warren Publishing in November 1971 when artists from the Spanish agency Selleciones Illustrada started appearing in the their three horror magazines, Creepy, Eerie and Vampirella. Maroto's first story, "Wolfhunt", appeared in Vampirella #14. Maroto quickly became one of the most well known and critically acclaimed Spanish artists at Warren. He would eventually draw 101 stories for them, more than any other artist except Jose Ortiz. Maroto won the Warren Award for best artist/writer in 1972, and his story "A Scream in the Forest" won the best art in a story award in 1973. Maroto remained with Warren until its folding in 1983.
Two Maroto's series were reprinted in Eerie and Vampirella. Manly, renamed Dax the Warrior, was reprinted in issues 39-41, 43-50 and 52 of Eerie. All of issue 59 was dedicated to Dax, which reprinted again the majority of these stories. His series Tomb of the Gods was reprinted in Vampirella issues 17 through 22.
He later worked on the series Amethyst, Zatanna, Atlantis Chronicles, The Savage Sword of Conan, Cadillacs and Dinosaurs, Dracula: Vlad the Impaler and X-Men Unlimited. In Italy, he worked for Sergio Bonelli Editore's series Brendon.
Comics work (interior art) includes:
- Amethyst #1-4 (miniseries, 1987–88)
- Atlantis Chronicles #1-7 (miniseries, 1990)
- Dracula: Vlad the Impaler #1-3 (miniseries, 1993)
- Zatanna #1-4 (miniseries, 1993)
- Savage Sword of Conan (Red Sonja) #1 (1974), 225, 230-233 (1994–95); (Conan) #217-218 (1994)
- Savage Tales (Red Sonja) #3 (1974)
- Vampire Tales (Satana) #3; #4 (1974)
- X-Men Unlimited (Hellfire Club) #33 (2001)
- 1984 #1-6, 20-21, 24-28 (1978–82)
- Creepy #46-47, 49-54, 64-65, 73, 80-82, 88, 92, 95-97 (1972–78)
- Eerie #36, 38-41, 43-48, 50, 52, 57-59, 63
- Vampirella #14, 16-18, 20-27, 31, 34-42, 45, 49-50, 53, 57-58, 60, 62-63, 67-68, 71-72, 74, 93-94, 98-99, 102-103, 106-107, 111-112 (1971–83)
- Cadillacs and Dinosaurs #3, 6-9 (Topps, 1994)
- Verotika #3 (Verotik, 1995)
- Wizard Presents: Lady Rawhide #1/2 (Topps, 1996)
- Zero Patrol #1-2 (Continuity, 1984–85)
- Zero Patrol (vol. 2) #1-5 (Continuity, 1987–89)
- Conan the Mercenary [Illustrator]. Ace Books, 1980.
- Conan: The Treasure of Tranicos [Illustrator]. Ace Books, 1982.
- Conan: The Flame Knife [Illustrator]. Ace Books, 1981.
- Conan and the Sorcerer [Illustrator]. Ace Books, 1979.
- Wolff (story),in "Dracula" magazine, [Illustrator]. New English Library, #1-12, 1971-72.
Maroto was accused of plagiarism of some illustrations from Tarzan and Prince Valiant (Hal Foster), Idyl (Jeff Jones), Flash Gordon (Alex Raymond) and more others. However, the practice of copying other artists, or a "swipe (comics)," is a long time-honored practice in comic books. Fans have long enjoyed the detective work of spotting swipes.
- Fanzine El Wendigo nº 13, pp. 6-8, Agosto 1979.