Cantrips are level 0 spells that cost d2 or d3 power to cast. In order not to let them be unbalancing, they don’t train skill and are mostly useless, except in certain circumstances or for low-Pw spellcasters who can’t do much of the bigger stuff yet. ais523 suggests that good candidates for cantrips might be things that have little combat use, and whose effects could be duplicated by backtracking or other tedious things, but would be useful to avoid boredom. Given their cheapness, they should probably not train skills, and may not even need spell schools.

Most ideas for cantrips seem to be a little too powerful and would do better off as normal spells (and may be listed as independent YANIs for normal spells); however, those that seem like they would fit are listed here.

• Increase the odds of monsters dropping a corpse in the next few turns.
• Create an empty unlocked chest. (This would need some restriction so you can’t farm and sell them; perhaps you can only create up to 10 or 20 chests per game with this.)
• Mark a map square with a symbol, perhaps a comma, that is no different from normal floor but shows up on #overview and the normal map view.
• Deal some small damage, such as d5 or d6, to a nearby creature. (Acid Bubble from D&D is a nice corresponding cantrip.)
• Dig out a single square.
• Create a cancelled hostile yellow light. It cannot explode at you since it is cancelled, so it becomes an autonomous light source of radius 1, which can’t follow you down levels like a pet can. Killing it should not grant you any experience; otherwise this would be easily farmable.
• Light a radius 2 or 3 area permanently, like a weak form of the spell of light.
• Mage hand: you indicate a direction and the nearest item on the floor in that direction, assuming it’s under 100 weight or so, is brought to you and is placed in your inventory. This can be used > to get things out of pits.
• Create an illusion of yourself at your spot. The illusion never moves. Monsters that see it assume it is you and will attack whichever one is nearer (the illusion is instantly destroyed if attacked).

Metal and stone chests can’t be kicked open to break their lock.

It’s harder to force the lock on chests or large boxes made of metal, and increases the chance your weapon breaks. Additionally, the material of the weapon used to force the lock affects the result, if it’s used to pry rather than bash:

• Iron and metal behave as normal.
• Mithril is stronger than iron, and breaks less.
• Copper is slightly weaker than iron, and breaks a little more often.
• Softer metals, such as silver and gold, break less often but tend to bend. A “bent” weapon doesn’t actually become bent internally; it just loses a lot of enchantment.
• Wood is about as good as copper.
• Glass almost always breaks, and can break even if used to bash open a lock.

The castle chest containing the wand of wishing requires a special unique key to open (it can’t be opened any other way). The key is carried by a random lieutenant or captain generated on the level.

Pets will never pick up large, bulky containers, like large boxes, chests and ice boxes. For one, picking up a heavy bulky object is unrealistic for many humanoid pets; for another, usually when pets pick up large containers they are doing something annoying like moving around a stash container.

A certain type of chest (not a new object, just a specially flagged chest) that is magically protected; it cannot be opened, unlocked, be forced open, or destroyed until a certain monster on the level is either killed or leaves the level. Once it’s gone, the chest opens normally.

Special “cell” room. Only valid if one end of the room has no doors. It generates a line of iron bars across this end of the room, with a locked (iron if possible) door somewhere in the line. Independently, it may contain: a prisoner, a sink, a bed (if those exist), and 1-2 chests with random contents.

Jars, which are like tins except made of glass (or possibly, tins made of glass material, in object materials implementing variants). Generate quite often as chest contents. Possibly, what is in the jar is apparent just by looking at it.

Mimics are very likely to mimic chests, instead of random items most of the time.

Unless you are blind, all boxes are obviously locked or unlocked once you see them. There is no need to first loot a chest only to learn that it’s locked.