POWDER is a roguelike game, which is not a port of an existing roguelike. It is built around replayability and long term ergonomics, not short term learning. Author of this piece of software is Jeff Lait.

Changes:

Fireball and Cloudkill always explode at the end of their trajectory.
When you gain permanent intrinsics by evolving or lichifying, relevant temporary intrinsics will be cleared, preventing you from having a silver-tolerant lich. (Nathan Bogue)
Timestamps on the final character dump and the description of how long you lived will now match. (Deozaan)
You can wish for bones and corpses without them instantly dissolving. (Garron)
You can no longer fetch items that have teleport fixed. (Eris Discordia)
When a creature (un)polys into a gargantuan creature, it will now also push away monsters in addition to crushing walls. (Nathan Bogue)
Lich-form creatures that are undead no longer report it being your evil that was useless. (garron Bailey)
When you name an item, the menu defaults to naming the type rather than the specific as this is the usual scenario.
The floor of the kiwi room is now the proper floor tile.
Controled teleport onto the square you are already standing no longer reports that you are blocked, but that you decide to stay put.
Mysterious mapping of rooms fixed. Thanks to Kender and Mental Mouse for tracking this down – it has been annoying me for six years or so! (David Damerell, Eilu, Kender, Mental Mouse)
buildall.sh should work with –use-home-dir again. (garron)
The option menu no longer has Load. Instead it has Quit, which prompts you if you meant this. Loading is now only done from the main menu.
No experience for killing your pets.
Confirmation prompt if starting New Game with active saved game as one can easily accidentally overwrite it.
Some spells when mistargeted no longer waste your mana. Not all, so remain vigilant.
Cancelling your choice in the Wish menu no longer costs a turn.
Fix potential crash when you are killed by splash damage from a thrown item.

While the highscore is kept, save games are never preserved between versions. Please wait until your current character dies before upgrading.

http://www.zincland.com/powder/index.php?pagename=release