Hideo Kojima made it because someone else had already made a Metal Gear sequel without him. It turned out to contain almost every idea Metal Gear Solid would be praised for eight years later.
Follows: Metal Gear
What Changed
Guards patrol across multiple screens instead of staying put on one
Enemies gained wider vision cones and could detect sounds made by the player
Added a radar on a 3×3 grid showing the rooms around Snake
Added crawling, letting Snake pass through vents and under obstacles and move silently
Built a far longer, character-driven story around betrayal, with more cinematic radio conversations
Key Facts
Released in Japan on the MSX2 on 20 July 1990, written and designed by Hideo Kojima
Made in response to Snake's Revenge, a Western NES sequel developed without Kojima
Set in 1999 in Zanzibar Land, a fictional state in Central Asia, in a world where the Cold War continued
Its stealth systems became the foundation of Metal Gear Solid (1998)
First released outside Japan as part of Metal Gear Solid 3: Subsistence (2005 in Japan, 2006 in the West)