Denial

Galefury has explained in Item Destruction why the 0.14 item destruction mechanic is bad. The basic reason is that it achieves very little (gameplay-wise) in most of the game, at a very high interface cost. There are places where it does mean something (i.e. works) — that's in portal vaults and (unintentional) Abyss visits —, but Galefury considers the general cost to far outweight these gains.

I concur, and 0.15 may have no item destruction at all.

However, I think that the basic idea of item denial is interesting. By this I mean that under some conditions, you cannot freely use your kit. Some examples of this:

• Silence disallows spellcasting (and some other things).
• Casting Ozocubu's makes you unable to use potions for a time.
• Lava Orcs (now removed) cannot use scrolls while on fire.

Some suggestions I've seen so far

• Fire attacks can deny scroll use.
• Cold attacks can deny potion use.
• Electric attacks can deny wand use.
• A way that denies/hampers god access (e.g. by increasing piety decay, and/or increasing piety costs). This has been suggested for a branch.
• A draining-type attack that only targets the leading skill (and stronger than draining does) while ignoring all other skills.

Why I think that such a mechanic can be good:

• There is a clear hierarchy how to go about problematic situations: First, avoid them. Second, get out before danger escalates. Third, use consumables (and don't be stingy with them). Scrolls like Blinking, Teleportation, Fear, Fog and the tactical potions have standard uses.
• Disabling something will make different (perhaps otherwise marginalised) choices more relevant.

One objection to the fire/cold based denial of scrolls/potions is that it's too drastic. (It is much more harsh than 0.14 item destruction: whereas in 0.14 you fear the loss of a potion or scroll, but you can use all other potions/scrolls just fine.) However, the idea can be made less coarse. Some (independent) ideas how to make denial more gradual:

1. Fire/cold attacks don't disable all scrolls/potions but only some of them. (In a way that's independent of the total number of potions/scrolls carried, of course.)
2. When under “fiery” or “icy” status (after attacks of that type), you can use scrolls/potions, but at a significant drawback. Delays are problematic, as the Blurry Vision history has shown, but there are other options: confusion, rot, stat loss, MP loss, noise (“you scream in pain”) etc.
3. When under “fiery” or “icy”, you use up two of the item (recall that in 0.15 you will be able to carry all that you want).
4. Under icy status, using a potion exposes all your potions to possible destruction (and ditto for fiery and scrolls). Flavour: you had to open your coldproof potion holder or fireproof scroll holder to get the item you want out — DracheReborn 2014-05-23 13:44

There might actually be a way to bring back proper item destruction, provided we can avoid its pitfalls. Here is one attempt — dpeg 2014-06-03 16:17

• basic concept: a monster with a fiery/icy attack which, unless killed quickly enough, will destroy an appropriate item
• scumming prevention: targeting inventory (or also floor items of the current level) are still prone to player avoidance, so I suggest something like a curse (this would be a good effect for a mummy): the monster will address one particular type of item (e.g. scroll of blinking), and a number of those. If you have that many on you, they disappear; otherwise, they disappear the moment you pick them up. There is no way to work around this (so you are best off just carrying all of them anyway).