Create a cover art inspired by the 80s and 90s Warhammer Fantasy, using the texture of chalk and charcoal printing combined with ink. Set the scene with a black background to create a dark and foreboding tone. The central figure should be a skeletal warrior in elaborate medieval armor. Surround this figure with other skeletal characters in epic action poses, capturing a sense of dread and the haunting atmosphere of an undead advance. Use a dark theme with predominantly black, dark grey, and deep, muted colors like dark blues, deep reds, and purples to reflect the grim setting. Use dramatic lighting to highlight key features like glowing eyes in dim, eerie colors such as green or blue. Incorporate subtle elements like smoke and flames in the background to enhance the sense of an apocalyptic scene with hints of dark orange and red from the flames. The overall imagery should present a chilling and captivating portrayal of a relentless undead force marching forward.