Nightmare Creatures

A single-player only game, Nightmare Creatures allows the player to control either Ignatius or Nadia. Secondary weapons such as pistols, mines, fire bombs, and magic spells can be used in addition to each character's primary weapon. The game features an adrenaline bar which causes health to be lost if it runs out, and players are forced to continuously seek out and win battles to keep the adrenaline bar full.

The story behind Nightmare Creatures draws upon gothic horror elements of the 19th century and begins in 1666, when a devil-worshiping cult called the Brotherhood of Hecate were conducting sinister experiments in London so as to take over the city, and then the world. The Brotherhood tried to develop an elixir that would endow them with superhuman powers. However, rather than creating their intended superhumans, their experiments instead created grotesque monsters called nightmare creatures. When they decided to use these creatures as an army of conquest, one of their members, Samuel Pepys, set their headquarters on fire, resulting in the First Great Fire of London.

The game takes place in 1834 when London falls victim to several evil occurrences. Monster sightings are reported along with news of people mutating into ungodly creatures, and that the dead are waking from their graves and walking among the living. All of London is in a panic and vulnerable to the schemes of Adam Crowley (who was based on occultist Aleister Crowley), a mad scientist and occultist enlisting the help of the Brotherhood.

Nightmare Creatures was the first video game to be created with LibSys, Kalisto's own proprietary 3D development program. The game's environments were modeled from 19th century maps and blueprints.

Nightmare Creatures was a commercial hit, with global sales above 1.5 million units by January 2000.

The PlayStation version of Nightmare Creatures received "favorable" reviews, while the Nintendo 64 and PC versions received "mixed" reviews, according to the review aggregation website GameRankings.