ABOBOBO

Killing Time (3DO). Studio 3DO, 1995. Cover artwork by the master Iain McCaig, known for, among other things, his conceptual artwork for the Star Wars movies and his Fighting Fantasy gamebook illustrations. (Source)

"One of the creatures designed by Yūsuke Takayanagi / 高柳祐介(Zeiram 2) and his assistants for the 3DO game N.O.B. Neo Organic Bioform." (Source)

Plok! (Super Nintendo). Software Creations, 1993. Clay models by Steve Lang. (Source)

Kow Yokoyama models in the Super Stadium instruction manual (also used for the box art). Developed by Affect for the Super Famicom and released in 1991, Super Stadium was rebranded as Nolan Ryan's Baseball when it was released in NA the following year.

Minelvaton Saga: Ragon no Fukkatsu (Famicom). Random House, 1987. Cover art by Hitoshi Yoneda. (Source) Regarding the advertisements, the artist is uncredited but the models are reminiscent of Kow Yokoyama's work on Xanadu. (Source)

Rainbow Islands: The Story of Bubble Bobble 2 (Famicom). Taito, 1988.

Juvei Quest (Famicom). Birthday, 1991. Fold-out map/poster included with the game. (Source)

Doom concepts and textures from the sketchbook of Adrian Carmack. (Source: 1 | 2)

Escape Kids (Arcade). Konami, 1991. (Source)

Cover art for Shiten Myooh (Mega Drive, 1990), also known as Shadow Blasters in North America. Developed by Sigma Pro-Tech. The artist is unidentified.

Advertisement for Blue Almanac (Mega Drive, 1991). The illustration, by Katsuya Terada, is also used for the box art. (Source) A US release was advertised as Star Odyssey but cancelled. However, Super Fighter Team eventually acquired the rights and published the game as Star Odyssey in 2011. (Source)

Relics (PC-98). Bothtec, 1986. (Source)

Street Fighter II promotional artwork by Akira "Akiman" Yasuda. (Source)

Air Fortress (Famicom). HAL Laboratory, 1987. (Source: 1 | 2)

Genpei Tōma Den (Arcade). Namco, 1986. Illustration by Katsuya Terada. (Source)