Melvyn Grant (born 1944) has had quite a long career in paperback cover artistry. He burst on the scene in 1975 in the U.K. and really hit his stride in 1977.
The was a sword and sorcery boom going on at the time and Grant was in the middle of it. He did a great cover for the Sphere edition of Tigers of the Sea and Andrew J. Offutt’s The Sword of the Gael.
Even L. Sprague de Camp was the beneficiary of the late 70s sword and sorcery boom as his The Tritonian Ring was reprinted. I don’t remember the scene of headless swordsmen marching forward. It has been a while since I have read it.
Grant did the covers for Robert Holdstock writing as “Chris Carlsen.” That is an interesting series. Holdstock was working with ideas that would later show up in his “Mythago Wood” series.
My favorite novel by Andrew J. Offutt is his homage to Alfred Coppell in My Lord Barbarian (1979).
The art is bright and dynamic. Grant went on through the 1980s, 90s, 2000s including doing some covers for the U.S. market. Most noteworthy was his cover for Charles de Lint’s The Fair at Emain Macha for Tor’s short lived doubles series. De Lint’s novella is one of the those rare reprints from the small press of the 1970s and 80s. De Lint wrote some sword and sorcery stories with a Celtic background before transitioning to his more famous urban fantasy.
Addendum: I was at Pulpfest this weekend just north of Pittsburgh. Jim Steranko was there and I talked with him about 10 minutes. He got animated talking about his barbarian illustrations. He told me he had each character use a different weapon. He also based them on tough guys from his neighborhood growing up. He said these were guys you did not look directly in the eyes or “they would take you apart.