Solomon's Key

Solomon's Key (ソロモンの鍵 Soromon no Kagi?) is a puzzle game developed by Tecmo in 1986 for arcade release on custom hardware based on the Z80 chipset. It is better known as a 1987 port to the Commodore 64 and the Nintendo Entertainment System, although it also appeared on many other game systems of the time, like the Sega Master System in 1988 and the Famicom Disk System, released in Japan on January 25, 1991.

The game is generally recognized as one of the most difficult games to appear on the NES. The player, controlling a sorcerer known only as Dana must overcome unlimited enemy spawning, challenging level designs, a countdown timer, instant death from any physical contact with enemies, and limited ways to dispatch enemies. In addition, it is easy for players to unintentionally render levels unwinnable while playing them. There is no saving, so if all lives are lost at level 49, the game has to be restarted from the beginning. However, a cheat code allows the player able to continue at the level where the last life was lost, except when used past level 41, in which case the player will restart at level 41. Solomon's Key has many hidden items and secret levels that are hard to find which enhances the reward for playing. The ending slightly changes depending on which secret levels, if any, the player finds and completes.