Dark [Alpha 26]

This update adds the Dark dungeon.

I wanted to see what adding a field of view algorithm to the graphics would look like. It created a more traditional roguelike experience that emphasised exploration. Whilst it didn't fit the existing dungeons and puzzles, it was certainly worth building a new dungeon around.

The Dark dungeon is the hardest dungeon so far. Ambushes are common. Forward planning is required to overcome the pieces which are all variations on the walker - it punishes players who kill everything before moving on. There are power ups hidden in treasure rooms that offer a big advantage, but there is also a chance for a wall-walker to spawn in them. The dungeon uses other mechanics that have been waiting for a chance to shine, the swap-trap in particular is a vital resource for defeating walkers.

I will tweak some numbers based on feedback and fix any bugs, but otherwise the Dark ready to play.

There are also some small bug fixes with this release.