When you call to mind the best games on the Genesis / Mega Drive, chances are 1993's Dinosaurs For Hire won't be too high on your list.
Based on Tom Mason's comic book of the same name and developed in North America by Sega Interactive Development Division, it launched to lukewarm reviews – but, according to a 2007 interview with Sega-16 (as spotted by John Harrison), things could have been even less appealing.
Programmer Steven Lashower reveals that the game was changed dramatically when the team was granted access to a pre-release version of Gunstar Heroes, back when it was still going under the title Lunatic Gunstar:
The original design called for these huge dinosaur enemies. The problem with that: they ate up the majority of the cartridge space and took up quite a bit of screen real-estate, not to mention the game was plagued by “sprite drop out.” One day, Jack Loh brought in a copy of a Japanese shooter for the Genesis called Lunatic Gunstar. After seeing that, the team shared this universal thought: “Boy, were we completely jacked.” We rushed to downsize the enemies to fit more of them on the screen as well as to make them more nimble. I think the only level that pretty much stayed the way it was designed is the level where the dinos smash and stomp all the little toy cars and tanks.
Released in 1993, Gunstar Heroes pushed Sega's 16-bit hardware to its limit; you can read about its creation in Harrison's excellent feature here.