NetHack Fourk is a NetHack variant based on the NetHack 4 codebase but with a more experimental approach to game-play changes (but still conservative compared to heavily modified variants like Slash'em and dnethack).
In addition to the NetHack 4 interface and AI enhancements, Fourk has made a number of gameplay changes. These fall into four major categories:
- Balance adjustments, intended to improve the overall balance and difficulty curve of the game. Things like alignment record, to-hit calculations, experience requirements, etc. have had the shape of their curve adjusted, and some game features have been buffed or gently nerfed so that they fit better into the overall scheme of the game's balance, as the variant creator envisions it. Some of these changes have been more successful and well-received by players than others; some of the less successful ones have been backed out.
- Monster/class reorganization. Some classes with very few monsters have been combined and thus freed up, and some heavily overloaded monster classes have been split. Some monsters have switched from one symbol/letter class to another one where they fit better. Additionally, some monsters that were formerly represented by punctuation marks are now represented by actual letters. For example, leprechauns are now i, and everything that was formerly : is now l (stands for lizard).
- Differentiation and variety. Some monsters, items, or special levels that were practically identical have been tweaked slightly so that they are no longer quite so closely the same. Some special levels have entirely new versions, as well.
- Consolidation. Some things have been removed on the grounds that they didn't really add that much to the game. (For example, there are fewer types of polearms than in vanilla.)
For a detailed list of changes, see the changelog (under External Links, below).