DOS Games made for DOS require an emulator to run on Windows. Use DOSBox or a frontend like D-Fend Reloaded and read this guide to play DOS games on your Windows PC.
The game had an add-on pack released called Bloodwych: Data Disks Vol 1 (AKA Bloodwych: The Extended Levels).
A modified map for the first level of the game was produced as a demonstration level, and featured on the coverdisk of Issue 1 of the ST Format magazine.
Bloodwych was followed in 1994 by Psygnosis' Hexx: Heresy of the Wizard.
The above text is licensed under the GNU Free Documentation License. This text is based on this Wikipedia article.
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