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I like the Orcanth thread for ideas, but I was thinking of the mechanics of implementation. I like the idea of wonders that may or may not require essence, or some other cap or limit. I also like set building design pieces that require essence. To make an impenetrable wall you add 10 segments each 1/10 of a mountain high to bridge a gap between mountains. Ditto with the tower.
What I'm wondering at the moment is: Should you build these wonders that require essence in one go, or should they grow over time? Say building Orcanth from your design would take 30 essence and 15 turns, but you could see the building raised from the ground up. Your sov staying put for the duration of construction, construction disturbed if your sov is forced to move.
A tower with 10 sections would grow with 9 non functional designs and a final functional one... that way you could see how someone design is growing and try to stop them from completing it. Maybe they should glow as well, shine with lights and flowers and white clouds... or cover the land in thunderstorms and darkness and a pulsating blood red aura. Just something to signal someone doing something dramatic... but not with 1 per player, non-magic wonders. I'd assume if they were designs you pick from a list any unique essence building would be one per game or just limited by essence cost.
Either way I liked it in Alpha centauri, building something like perimeter defence force or probe nexus or human genome project. Maybe some unique buildings could be:
"soul forge" A magic forge and giant golem, infused with life stealing essence. cuts your population growth rate by 25% but causes all swords forged to contain fallen souls (unique graphic, large bonus) destroyed when captured by a good race, neutral golem released. used against you by an evil race. (choice upon capture?)
"Glade of cleansing" A mix of magical animals are born in this glade, anyone who enters is restored completely and any darkness in their soul removed. Causes pop growth to increase, production to increase and removes spies from territory. Destroyed and all creatures slain (evil), Pool tainted and creatures warped to evil (also evil), creatures bred for war (neutral), pool captured (good)
"Golem Workshop" Built upon a mine (type for type of golem to be able to be built), the sov uses his own life force to create sentient anamatrons, shaped by artisans and each infused with a drop of blood using an orb of power. initial essence cost for the building only or per unit cost on construction or per unit cost *on unit death*? Each golem is designed for a particular function. On capture the function can change, or with the will of the sov:
Evil: use cheaper resources for these units, no essence cost on unit death/construction, instead have a population cost say 1k or 10k or 1 city level or whatever. Used for warfare
Neutral: Destroy the orb, weaken the controlling sov on capture or keep it as normal, essence cost, war golems.
Good: Make the golems help the people, +%production +%build rate per golem built.
"Elemental transformation" Bind the power of a manashard into human hosts. Creating elemental beings able to live permanently without a mana cost. Not every attempt is successful however and the power required to tame pure fire into living flesh requires a piece of the soul of your summoner (sov.). Allows elementals as a trainable unit, each requires 100/1000 men, high cost, high power, build over mana shard. (cheaper units if shard can no longer be used, much more expensive units if mana shard functions normally in mana production.)
Evil: Use the soul fragment to create one ultimate elemental
Neutral: as above
Good: use only the pure and the willing. Lower cost elementals and larger training time, provides a large non-combat benefit based on mana type.
"Living Songs" Art so beautiful it attracts talent from over the world. Paintings that live out stories and sculptures that enact battles. Poetry that writes itself and sings through the streets. ++Prestige, ++research (attracts talented) -production/-war production (encourages pacifist tendencies)
Evil: Tormented souls scream through the streets, artwork on every wall depicts vile torture and sculptures in the town square torture the weak and pure of heart. ++production, -prestige, +research (increases productivity) +amazingly cool factor
Neutral: destroy
Good:default bonus
"Baby demon" Use essence to summon and magic to confine a demon to your cause. While caged it can be used for magical research, although it will need to be fed the souls of your minions if we want to be able to use it for battle. ++magic +research, -prestige, -% growth rate. In x turns the demon will become a lesser demon, bonus increase, penalty decrease, a further x turns it will drain more mana to confine and eventually must be released, destroyed or used in your army. Adult demon can be controlled, immature versions escape as a wild monster with a mana deficit for 3 turns. (need a little period of grace to recapture a mana shard) On capture:
Evil:use in army/release into enemy lands
Neutral: release the demon to its home plane (grants a wish)
Good: Destroy the demon and cleanse its ruinous form (battle with demon, gain 'demon slayer perk' or item scavenged from corpse
"Living forest" You create a guard of living trees to provide wood for your needs and food and, should the need arise a slow but sturdy army. +wood production +food bonus
Evil: curse and warp these trees to give them power. +trees upgraded to dark war trees, able to poison, no longer produces food, lower wood production
Neutral: Free the trees - gain sight bonus in all woodland around your empire, neutral trees wander map
Good: Work with the trees to spread forests and restore the land (original bonus)
"Minotaurs maze" Unseen and unheard, a maze ensnares the roots of your city. Within it you train both the heroes of the land and your new breed of creatures. Produces Minotaurs and increases the rate of finding or heroes.
Evil: Boos production of both with human sacrifices +benefits -production
Neutral: as above
Good: Phantom minotaurs instead of real ones, keep the hero bonus, no minotaur production. On capture, free the minotaurs. Generates goodie huts in territory or creates a new minor race.
"Living citadel" Your citadel is linked to your soul, it follows you to your death. At any time you can call the citadel to your current city with only a moderate mana cost (and short cooldown). +tactical benefits, and magical benefits of citadel
Evil: Soul link. You can join your citadel with a city you are sieging. Resulting in confusing battles and no defender advantage, massive siege engines and citadel benefits (mana cost, reinforcements) But risk of total and utter defeat - no retreat at all possible. Happens every time sov attacks a city.
Neutral choice: Functions as original. Destroy citadel when captured.
Good: Your citadel has free reign and is not bound to you, it can move at will to other cities allowing for interesting fast travel and defensive options.
Anyway, basic thoughts are that unique buildings should have an event upon building or upon capturing, to set the benefit and the costs. I'd like the two situations to be different, so that you may put off building a certain wonder if you could get something fun to happen if you capture it instead... or just be encouraged to attack an empire not to deny them the benefit but because you could get something better. Maybe event linked ones should only happen once... one creation event, one switching event max. Except for specific events. (how the ring of power is used for example, destroying it would be once off, same with creating it. Using it to create a wraith/prolong life would be repeatable. Some events may be repeatable and need to be set each time, building iron golems, stone or adamantium golems for example, each would have its own event. And be repeatable.