Scumming

In roguelikes, scumming is a strategy that consists of collecting easy rewards with low risk, e.g. when a high-level character visits levels suitable for low-level characters since they pose no risk but do offer some marginal rewards.

Scumming was prevalent before version 0.6.0. Players would spend thousands of turns waiting on early levels for monsters to respawn, kill them without any risk, and thus raise their level beyond what was reasonable for that area. Mummies benefited the most due to their lack of a food clock. This rewarded tedious play behavior, and trivialized later branches since players entered them with a higher level (and power) than intended.

Players can still scum in Crawl due to the infinite nature of the Abyss and Pandemonium. However, they have to fear dangerous and hard to cure mutations. Also, characters who can stay in these branches for extended periods of time are likely able to win the game.

Finally, the game has a hard limit of about 200 million turns. If you reach this limit, your game ends with the message:

Outside, the world ends.
Sorry, but your quest for the Orb is now rather pointless.
You quit...

Start scumming is a form of metagaming; restarting until you get a good start. Some species and backgrounds have a degree of randomness to them. Draconians may want to get an optimal colour - but they often have little impact on a game. Demonspawn and Djinni may want to restart for a better mutation or spell set, but both take longer to settle in. Finally, Wanderers and Delvers may want to restart after a better start. Keep in mind that this counts towards your winrate.

History

• Between the removal of the food clock and addition of the Zot clock in 0.26-trunk, players could abuse Xom to gain lots of beneficial mutations.
• Monsters stopped spawning post-generation as of 0.21 (barring both infinite areas and while holding the Orb of Zot).
• As stated in the article, 0.6 made out-of-depth spawns a constant force to keep you moving. After more than 3,000 turns on a given level, the number of monsters that would spawn gradually decrease, until monsters stop spawning altogether after 15,000 turns. Additionally, these monsters would be extremely out of depth.
• In an unknown version, stats used to be randomized: there were eight stat points that would be allocated randomly, potentially encouraging restarts.