Crispy Heretic is a conservative, historically-accurate Heretic source port, which is compatible with mods and levels that were made before the Heretic source code was released. Unlike other source ports, the goal is to preserve the original look, feel, limitations, and bugs of the original DOS executable.
Full support for single- and multi-player games is provided. Unlike the original executable, network play is implemented on the IP network stack, allowing it to function on modern LANs and the Internet.