New monster ‘chicken’, added to the c monster class, but it is a normal chicken with no special attributes or powers. Eating its corpse gives some chicken related YAFM, and wielding its corpse and hitting a monster with it may make them flee; a comment in the code should indicate that this is because they are “chickening out”.
Make the invoke effect of the Tsurugi of Muramasa enhance it to give double damage for a limited time, but also become bloodthirsty during that time. For an immediate effect, it could also cause fear when invoked.
Eating a monster in front of a monster of the same race freaks them out and causes them to flee.
Bisecting a monster with the Tsurugi of Muramasa should have a chance of scaring nearby hostile monsters into fleeing.
The Helm of Terror: an artifact which is some unspecified type of helm, which automatically frightens all living creatures that have eyes.
New object property “of fear” or “of terror”, which is only valid on melee weapons. When a weapon of fear or terror hits a monster, it may scare that monster. If a player fear system is implemented, it also scares the player when they are hit with it.
Defeating the quest nemesis causes a “rout”. As a temporary effect, monsters that are part of the normal quest generation flee from you.
Grimtooth can be used to engrave a special name, similar to Elbereth, that scares only elves and hobbits.
Invoking the Tsurugi of Muramasa causes a fear effect similar to reading scare monsters and gives a temporary effect equivalent to increase damage (possibly only on hits made with the Tsurugi, possibly with any weapon).
It was also pointed out that triggering a temporary effect by invoking could get tedious. Another suggestion was to give it some sort of passive fear-causing effect when wielded (in addition to the one-time scare when invoking it).
Eating a clove of garlic causes, or can cause (not necessarily a 100% chance), monsters on the level to flee from you for a little while, identical to the “bad breath” fountain quaff effect.
Monsters should be immune, or less likely, to turn to flee if you have aggravate monster. This should probably only affect monsters fleeing after being harmed in combat, rather than all forms of scaring.
The stated goal of this is so that Knights who are tired of taking caitiff penalties on fleeing monsters can give themselves aggravate monster to sidestep the penalty.
When you cause a monster’s mount to become scared, there is a chance that the rider gets thrown off, possibly taking some damage. This also happens to the player if their steed gets scared.
Artifact whistle Nightingale, based on the Nightingale Robber from Russian folklore. When blown, it causes various effects to monsters in a sizeable radius: stunning, confusion, scaring, possibly even instadeath if they are weak monsters or have low HP (or just HP damage). Any of those effects can also happen to the player. The player is guaranteed to become deaf for several dozen turns from blowing the whistle.
As a limiting factor, it will only cause these effects if blown when its invoke timer is ready, and blowing it will internally set its invoke timer as if you invoked it. If blown when its invoke timer is not ready, it will just behave like a regular whistle (and no “ignoring you” message will be shown).
When you cause a Yendorian Army monster to flee, nearby lower-ranking monsters may also flee. Possibly extend this to other ‘pack animals’ such as orcs or ants.
Make a radical change to the scroll of scare monster, making it no longer scare monsters on the ground; instead, boost its reading effect to a very powerful scaring effect, more so than can be accomplished with a horn.
A much more fleshed out interaction system for sapient monsters. It is initiated by chatting, which opens up a menu offering four key verbs: Ask, Tell, Show, and Give.
Ask is used to gain information from a monster; this could be a whole bunch of things, from rumors to identification to information about the dungeon. Each type of monster you can ask things of has a limited knowledge base, and this knowledge base may contain some inaccurate information. Especially interesting is the possibility that you can ask someone for identification, and they tell you what they think it is - which could be right or wrong, but a good clue either way. You can also ask someone to join you, and pay them some gold to tame them for a certain amount of time.
Tell is currently a less developed part of this idea; the only thing suggested so far is that you can tell a creature about traps you’ve discovered, which will make those traps known to the creature. You can also use “tell calm” on your pets to make them refrain from attacking peacefuls.
Show lets you select any item from your inventory to show to the monster. This can be used for intimidation (e.g. showing a stack of iron skull caps to a goblin).
Give lets you give items to a monster, which in some cases, depending on the AI, lets you test the effects of items.
Note that a potential pitfall of such a system is that if it’s complex enough to do interesting things with, it is probably going to be hard to use without spoilers. And if it’s uncomplex enough, it runs the risk of most possible responses being “I don’t know/care about that”, which also makes it hard to use without spoilers. A middle ground between these is likely to require an enormous amount of work.
“Awe” intrinsic, granted only as a divine boon for a short duration: any monster you hit or that attacks you automatically gets scared.
When you are crowned, your character gains a literal ethereal crown above their head that causes hostile monsters of (significantly) lower level than you to have to pass a resistance check upon seeing you or else flee.
Eating garlic replicates the effects of the fountain effect “This water gives you bad breath!”, causing all monsters on the level to flee for a limited time.
Monsters can drink potions of booze as a defensive item, but only when fleeing. It cancels their fleeing and confuses them.
Mindless undead are immune to every form of fear effect, including scare monster.
Note: EvilHack takes this a step further and makes every mindless monster immune to fear, not just undead. This may be more apt, depending on your point of view.
Fleeing monsters may randomly get a few bonus movement points each turn.
Undead in Sunsword’s light radius will flee.
Ideas about nerfing the player’s ability to scare off a large group of Yendorian Army troops at once:
This doesn’t necessarily have to be only the Yendorian Army; the rule could be extended to all monsters being “supported” by other monsters of their same species, with some special cases for things like all orcs supporting each other.
The various Banes scare their target type of monster on top of the extra damage they deal them.
Polymorphing into a big scary monster like a dragon or minotaur causes some monsters (failing a resistance roll?) to flee.
Certain monsters (e.g. the Riders) shouldn’t be able to be frightened by getting a ghost from a bottle.
New artifact The Phial of Galadriel. It is a potion of water (potion of starlight in dNetHack) that acts as an infinite light source which scares giant spiders and Nazgul that come into it, and can be invoked to bless 1 item. May need more powers to make it better, and behavior for what happens when you drink it, but these are unspecified.
New artifact Aegis: is a bronze roundshield (which is supposed to have Medusa’s or another gorgon’s face impressed on the front). Can be invoked sideways at a monster, which petrifies it or, failing that, causes it to flee (regardless of difficulty or monster MR). Can be invoked downwards to burn a Gorgoneion in the floor. Possibly grants stoning resistance or gaze resistance while equipped.
