Crypt Killer, known as Henry Explorers (ヘンリーエクスプローラーズ) in Japan, is a light gun shooter game developed and published by Konami in 1995 for Arcade platforms. It was also released in 1997 for the Sega Saturn, Sony PlayStation and PC. The Saturn version makes use of the Saturn's various light guns, while the PlayStation version is compatible with the Naki Lunar Gun and the Konami Justifier. The game's scenery and characters are all rendered with 3D polygon models, while most of the enemies and their projectiles are 2D sprites.
The players are "crypt raiders" guided by Galazon, the spirit of travels, who resembles a floating head to travel through variously themed caves, temples and crypts in search of the "Eyes of Guidance" which would open the doors of fate. On their journey they are armed with a shotgun to fend off many mythical enemies, some very reminiscent to those found in the Castlevania series, such as bats, mummies, skeletons, fish-men, gargoyles, Medusa, Hydras, levitating swords and many more.
One, two or three players simultaneously travel through levels "on rails", as in the vast majority of light gun shooters. At certain points on each level the players choose their path by selecting to go one of two different ways. The opening screen allows the player to choose from any of the six levels. There are three areas (besides the boss area) per level. At the end of each level, the player encounters a boss guarding the "Eyes of Guidance" needed to progress. The player can temporally upgrade their weapon by finding concealed more powerful guns such as a Gatling gun, grenade launcher, a more powerful shotgun, and an automatic hidden behind breakable objects. In the console versions, for each life the player has three bombs which can destroy all enemies present on the screen.