The Future: The Supernatural
Deities, Powerful Allies and Patrons: How do you meet/find/experience/whatever them? What do they demand in return for power? What powers do they grant? How do they grant them? Many of these questions can be answered by the ideals that a deity aligns itself with. Deities can be set in opposition (Truth/Lies, Nature/Undeath, Honor/Tyranny, Life/Disease, etc.). Deities often have many names in different civilizations. Cults and religions can grow up around powerful beings. Some of these beings might demand sacrifices (as a matter of course, for perceived infractions, etc.). Sacrifices may or may not actually maintain or increase the power of the being. Prayers of mundane followers might actually be answered in certain cases. It might be appropriate for a creature to give thanks to its deity at certain times.
Forces: These are things like "the elements", the spirit of a forest, or the psychic remnants of a lost civilization. They act like deities basically, but may not be sentient. Towns might have local spirits that can exact retribution for violent acts, etc. Note that any elemental planes could just consist of one driving force, or they might be as complicated as the normal world with inhabitants, items, entities, and everything else (perhaps even many magic types within the standard elemental art). Regional forces might be able to compel the natives of their region to act in certain ways. Forces may also be able manifest in different ways (as a single powerful being, a mist, a multitude of fairies, etc.).
Some Desired Spell Types at the Empire Level: Make Equipment / Resources / Creatures / Structure, Summon Creatures, Enchant Equipment, Heal, Enhance Creatures, Damage Creature / Equip / Terrain / Structure, Alter Terrain, and Enhance Structure.
Channeling from Other Worlds: If the universe has elemental planes like "the fire plane", then there will probably be wizards that can bring in elemental fire from the fire plane or travel to the fire plane. This involves some notion of portals. There can be point conduits and area conduits with various restrictions on them. Basic portal types include: Closed, Free-willed Entry/Exit, Controlled Entry/Exit, and Uncontrolled Entry/Exit. Portal variables can be altered, and portals can be set to move (so you could have a moving geyser of elemental lava, for instance). I'm also toying around with the idea of graspable portals (if it is set to suck in those that it strikes, it might make an interesting Frisbee... that lava geyser might make an interesting Frisbee as well). The rate at which a portal opens and closes is also important. Portals also have rates/forces of pull when they are trying to extract elemental matter (or snatch things from the caster's plane).
Behavior of the Elements: If the universe includes elementalists, then they will have different concerns with the behavior of their element. For example, if a portal is opened to the lightning plane, lightning might shoot out of it chaotically and be difficult to control. On the other hand, a portal to the earth plane might yield nothing at all - the caster might need to expend energy to extract solid rock from the other side. The upside is that once the earth is extracted, it doesn't zip around and fry your friends. Effects like this will add some flavor to the game.
The Bullet Problem: Spell casters that can move objects could just go around shooting people if velocity is unrestricted. So both mass and desired velocity will be used to determine spell cost for telekinetic effects. I suppose if the caster has very high skills and attributes, he or she can still go around shooting people. I don't have a problem with that, but I imagine the victims will.
Mental Spells and Psionic Effects: How do they work? I already have two structures in a creature: one for its soul (mental attributes/skills/etc.) and one for its thoughts (preferences, targets, etc.). So mind-reading spells should be possible, as well as spells that change thoughts (temporarily or permanently). It will be easier to affect the thought structure than the soul structure in most cases. Casters should be able to compel beings to perform actions, with the compulsion of less palatable actions (attacking friends, suicide, etc.) being more difficult to achieve. Powerful practitioners might be able to enthrall entire armies.
Curses: How do they work? What can they do? How do you get rid of them? Some curses might work by using items attached in some way to the curse recipient (a favorite weapon, or the skull of his or her father from the graveyard). The maker of an artifact might be harmed through the artifact (through some ritual, etc.). Figurines in the likeness of a creature might be used to harm it. Curses might be simple like: If you attack druids, your arm turns to wood - or they might be vastly more complex. The player could start with a curse (such as lycanthropy) and not know about it -- this could be very annoying (and sabotage an otherwise good character), so it would only happen rarely, or the player would be given sufficient clues, you know, like waking up covered with the blood of his or her victims. Curses can be structured using the same interface as a magical art. More curse ideas: kill in order to stay alive (get benefits while you do it, but are of course stigmatized, can be extended to vampirism), allergies, sword of damocles style, Midas touch, relive the same day/etc. until you do a certain thing (soul structure stays the same ie you learn, but physical state and items are reset as is your location and the rest of the world). Curses might be based on heredity. The player might become cursed by a mummy or dying opponent -- depending on the universe structure, every single dying opponent might have the opportunity to make a death curse. Items can be endowed with curses. Cursed weapons might attack their wielders. Events linked to major cursed items could be tracked, and these items could be given legends just as the players are (and like old player legends, ancient cursed items might contain inaccuracies or fabrications).
The Undead: I guess this might go under curses. With the species system I have, "vampires" and "zombies" can't be added in as additional monsters. So I actually have to go in and say how it works. In more standard universes, I can just put in the standard curses and how they work. In other universes, there can be a random curse generator, and some of them might involve the undead. Gods of the dead/undead can bestow the gift/curse of undeath on followers and others. All the standard things, and I'm sure the game will come up with things on its own once I put in some random elements for it to play with. There can also be undead that come about to avenge their own deaths - children killed by the player can come like smoke through keyholes, paralyze the player, and do some strangling and eye gouging. If a zombie or ghost is known to another creature (from when it was alive), that creature might recognize the undead (and possibly gain control of it, or just get really freaked out). Corpses in foul places like sewers might arise... just because. Methods for dealing with undead (valid or superstitious) will probably pervade areas where they are common - religious signs and symbols are often enough to deal with simple undead. Undead creatures guarding burial grounds might exact retribution for disturbances, and they might recognize creatures that are the descendants of the buried (either to let them pass, or to exact particularly harsh retribution). Evil magic can cause those that starve in a siege to rise as undead and attack the defenders from within (if the zombies are burned, hungry peasants under siege might be forced to eat the charred undead bodies - this can have all kinds of weird consequences). Destroying the undead is generally a task... burning, staking, holy water, silver, etc. Certain classes of controlled undead might be destroyed at the death of the controller. The player could be tormented by a ghost for some reason. The player might become a ghost after death until fulfilling some goal (most likely related to his or her cause of death or current quest). Standard zombies should be inclined to pound on doors and moan.
Otherworldly Summonables: An alternative to undeath is possession of corpses by demons (that is, it is not the original soul inhabiting the animated creature). The notion of summoning demons is important to this genre of games, and there should be some kind of "world" from which powerful beings can be summoned. These beings can be placated in any of the ways that other creatures are placated (control spells, gifts, unthinkable bargains, etc.), and they can be given any of the tasks of normal subordinates. In some cases, the world where the powerful beings come from will be a fairly standard one, just as any world where the player starts. In others, the creatures might be either idealized versions of the creatures in the main world (angels) or twisted mockeries of them (demons). The game will have some kind of idealization/mockery routine to make things either angelic or horrific in comparison to the original creature (things like halos, big feathery wings, no skin, skin stretched tight over bones, skeletal, burning hair, combination with "lower" animals - especially those that are either sacred or profane in the target culture, hollow eyes, etc.). The creatures whose forms are being idealized or twisted will have a psychological reaction at seeing the otherworldly creature if they are smart enough to understand and if they haven't faced such a thing enough to get used to it. Creatures can be summoned by spell casters, or they might simply be drawn into being by auras of pure evil, etc. Demons that mock a certain race might have knowledge of that race (able to call out creatures by name and render them powerless, etc.). If a summoned creature finds itself uncontrolled upon arrival, who knows? It might stay and hatch plots or just generally mess things up, or it might return home or just get lonely or something.
Effects of Exposure: Depending on the power source and the magical art, a spell caster might grow so attuned to (or be so corrupted by) his or her source of power that he or she physically changes. Elementalists are the most straightforward - for example, an experienced water mage might have translucent liquid hair and the ability to breathe underwater. Necromancers might be blessed/afflicted by a curse at some point, perhaps even that of undeath. Non-spell casters can also be affected by long term exposure, although the effects might not be so extreme. Exposure might even lead to a species change. Creatures can be exposed to magic itself or to magical items and beings. If the exposure is to something like pure evil, the exposed creature might become despised by non-evil beings that can sense its evil aura (and likewise for good). Inherently good beings exposed to evil auras might become ill or weak. Perverted swamp mages can grow gills out of the back of their necks. Creatures that are aligned with a particular force might act it out upon death (water mage melts into soil, etc.).
Time Altering Magic: This can get ugly. There probably won't be any time travel unless it is into the future or an alternate past. Basically, the past is hard to regenerate for these purposes. Other effects, such as slowing time or stopping it, are relatively easy. There should be weird effects if a player stops time and moves away from the initial casting point of the spell. There needs to be some mechanism for stopping abuse, anyway. Imagine fighting someone who can stop time - do you want the game to say, "The time wizard gestures. [Time stops. The wizard comes over and kills you.] You die."? That would be kind of anticlimactic. So there need to be heavy costs and/or heavy restrictions.
Sensory Spells: There should be spells that allow the caster to use the senses of other creatures, etc. Some necromancers should be able to look through the eyes of the dead (then they can hide dead rats everywhere for voyeur webcams). Of course, heightening one's own senses can also work (or attaching them to a spell cursor).
Dreams: There might be some kind of system of dreaming. This might also involve going into a creature's dreams and killing it there, etc. (it would be fun to program in dream worlds - they could be really messed up). The same mechanism might be used to facilitate player hallucinations, battles between souls inhabiting a single creature, etc. The forces of darkness might plant false dream premonitions in a creature's (possibly even the player's) head to accomplish some goal - sympathetic forces might plant helpful information in dreams, etc. Illusions can also be used for these purposes. There might be mechanisms in the game that force future events - then dreams can offer premonitions (this would also be handy to have around so that the game can generate actual prophecies).
Prophecies and Precognition: In general, it would be nice yet difficult to implement various forms of precognition.
Experiments and Research: Many types of spell casters must research to increase their knowledge and power. Some of this might fall in the category of "dark experiments": perverting creatures into other forms, working with evil artifacts to explore the depths of their powers, etc.
Hierarchy: Often times, a powerful mage can undo the works of a lesser mage. Sometimes this form of chastisement can lead to wounds appearing on the lesser mage, etc. In fact, there might be strange effects from any form of chastisement.
Metamagic: Metamagic basically goes in and messes with running spell programs, ether, auras, etc. Some metamagic effects: defuse a spell trigger, set off a spell trigger, calm ether (get rid of all imprinting/auras in area), amplify ether (make a general ether aura somewhere), chaos (cause random ethereal spell effects/triggers/etc.), detect ether disturbances and auras. Some metamagic might be restricted - a priest might only be able to use metamagical effects on auras created by deities, etc.
Rituals: Rituals are much like spells, but they can be used outside the spell environment (for coronations and other ceremonies, certain experiments, etc.) Ritual steps include: Action (arguments) - this is the center of the ritual, Input (type) - sets a target, Wait Until (cause), Delay (time). Actions include: Gesture, Kill, Cast Spell, Sound/Signal, Placement/Use of a Targeted Object.
The Afterlife and Reincarnation: I forgot if I wrote about this already, but anyway... the player could be a reincarnation of a previous player. In particular, this would facilitate persistent characters (like those in Fantasy Empires:) ). You could die and then play a second entire game in the afterlife, perhaps with the goal of being brought back and playing in the first game again (or something else entirely). The short version of this is that standard scenario in which the player plays some game of wits with Death and is brought back -- this general system could be made arbitrarily complicated, although too many complications might make the player not want to go back after having invested so much in the second area. Note that reincarnation/returning from the dead need not be restricted to the player. A mighty demon could return to plague the world 500 years after its initial defeat.
Magical Corpses: Monster pieces can have all kinds of magical properties. Especially when eaten:)
Shadows: Shadows often have some sort of mystique about them. Creature shadows in a given universe might reflect the presence of a soul or just be normal shadows. Shadows could be alive or animated.
Regeneration: As the creature bodies become more complicated, rapid regeneration becomes more and more subject to abuse, so it should be difficult. A character can remove his or her limbs and sell them if they are useful (much like the mutant body part harvesting in the novel Treason), etc. This isn't really a problem, it's just that regeneration is very powerful and will therefore be difficult to obtain.
Corpse Animation: Creating Frankencritters is fun. Depending on the world generation parameters, there could even be Frankenstein-style lightning animations, and so on. Severed body parts could become independent creatures in certain morbid cases.
Suggestion Spells: Spells that suggest/coerce certain actions to be performed by the target, or plant certain thoughts in their heads, can be facilitated by the conversation interface. Then complicated orders can be given, just as you'd talk to a subordinate.
Aura Musings: Auras can be created by, say, evil creatures or evil acts. Particularly strong aligned auras can attract co-aligned creatures, and repel oppositely aligned creatures. The aura generated by a powerful being might help its foes to seek it out.
Some Spells: Druids might be able to bend wood. Water mages might be able to desiccate their poor victims. Put wounded friends in stasis. Turn ground into mud and back again after some people sink in, or slick a cliff with mud in order to slide down. Grab someone and teleport away with them. Fell trees to make barricades. Detect all kinds of things. Graft body parts onto your body (if they belong to powerful beings, then perhaps you can channel their power, or attempt to contain their spirits within you). Create foul races (quite easy considering I already have a random creature generator - just add in a little interface and poof we have Johnny-orcs, or [playername]-orcs.): note that these races might make their appearance in future games, breed, form cities, and anything else other creatures can do. Make constructs. Quench fires or start them. Animate vines and strangle things (or do less aggressive things, if you can think of them). Make wood as strong as steel. Clench your fist and squash something ten feet away (if it's alive, there should be massive ichor seepage). Animate mud and twigs into ambling mud creatures, or you could mix your blood in and create foul mud creatures with poisoned ichor and bind them to your will. Redirect rivers to sweep away fortifications.
More on Possession: Certain dying creatures might be able to. Some metaphysics systems might have very involved systems of soul combat (perhaps involving the same mechanisms as dreams).
Spell Resistance: A caster might be knocked off balance if he or she misaims a blast of water (the blast might also fill up the section of cavern drowning all of the caster's companions). Structures can be made resistant to fire, etc. Some creatures are particularly susceptible to certain elements, etc. Other heroic, powerful creatures should be able to resist spell effects to some extent, especially ones that cause automatic death, etc. Peasants aren't so lucky.
Musings on Items: Powerful, intelligent items might control weak-willed creatures that possess them, although enchantments might exist in the world to counteract these effects. The maker of an item might be contacted or even summoned through some ritual applied to the item. Dying prayers over items can lead to sword-in-the-stone type situations. Items should be able to change into other items (a crystal on a staff that can be removed and changed into a crystal ball, a toothpick that changes into a club or a crowbar (just picking my teeth, officer), etc.). Items can store power (simple example being wand of fireballs), or an item can be a focus to assist or enable spell casting. Some spell casters might be powerless without an item of some kind. Pieces of powerful beings can stick around and become artifacts (these parts might have been cut from the beings in prior games). If an item is linked to a creature (possibly its maker), then it may disappear after the death of its owner (in a puddle of black caustic slime, etc.). Long rituals might be required to destroy powerful artifacts.
Spell Extras: If a caster overinvests in a spell (too much material etc.) there can be standard miscasting effects, ether bursts or some such thing, chaotic effects, or a proportional improvement to the spell (including added perks and refinement). Certain spells may have extra bells and whistles attached that can be added on for extra cost.
Some forum spell effects: sever, disarm/drop, repair sever w/ part, fatigue, create item, tear apart, squash, summon, blindness, fix grip to weapon, animate corpse/chunks, poly-self (could be free to imagination or fixed form), mood changing, sweeping beam of death, send enemy weapon to hand, shrink/enlarge,shred
Some forum magic musings: chant long time (ritual), thought character in thought rituals (like bad thoughts lead to effect), musical rituals, drawing diagrams with blood/silver dust, have spell where each creature slain give cumulative chance of own death, bad thoughts -> auras, prisons attached to items (destroy item/release creature), side effect -> equal mass of some fixed/random material created, some magic completely dependent on fields and flows, fields influenced by magic (happiness carvings, house heating carvings), magic attributes (eg the force) that pass through families.