Personally I think that having shards be easily defensible probably isn't the way to go.  It wouldn't necessarily preclude turtling, however it would force a player to turtle in a more realistic way.  The traditional turtle in a real-time strategy game is to hide behind your walls and defenses while you tech up.  Such a thing is not possible in real life, as such a strategy leaves all of your peasants to be slaughtered, your farmland to be burned, and your resources to be pillaged.  While such a plan can be successful (the French during the 100 Years War or the Russians with Napoleon) there are very significant costs associated with it.  A more realistic turtleing strategy should be more reactive.  Namely you don't attack others, however must dispatch armies to defend your holdings.  Perhaps building a castle or other style of fortification in the vicinity of the shard (or even around it) should be possible, however such a structure should be quite expensive because of a dearth of population in the area.

Choosing map settings is a fundamental part of every 4(5)X game that I've played. Why shouldn't the mobility of shards be a major setup decision when you start a game?

I've found *most* of the scenarios in this thread interesting, so I'd really prefer the released game to enable me to play one game where shards were like oil wells or uranium mines, another where shards were like crown jewels, and another where they were somewhat in the middle, perhaps like an Egyptian obelisk that a late-Republic general might have hauled back to Rome. Seems like such choices would generate an extremely wide range of play styles, and that any crazy folks managing to master the full range of settings would well deserve an Elemental Hero title of some sort.

I like this idea a lot!  I can also imagine it being very hard to code the AI to deal with all of these options.

Still, it would make for some interesting game variations so send troops deep into enemy lands to retrive shards (or shrads).  It does not need to be nearly impossible to get "turtled shards" back.  Options might include:

-the traditional storm the castle-the city might have the option give up the shard to spare pillaging of the city.

-a very good thief or other stealth units-perhaps with some magic buffs

-befriend a dragon (or other mega-monsters)-they could strategically strike the city

-dwarves that can dig under the city.

-other ideas?

The turtled city with the shard could try to develop defences against such assualts (magic alarm system, more walls, anti-dragon buildings (or magic domes over the city).  It would be too expensive to maintain all of these protections.  It could be an interesting cat and mouse situation.

Making them easier to steal or take would also encourage players to spread out their shard collection- even if they are movable.  It would be a terrible blow to loose them all at once.  Anyway, I would find games like this interesting.

How about simply representing the fact that cities can't feed themselves... they rely on the surrounding countryside and imports.  Cut a city off from those and eventually you will starve them out.

That assumes that a shard needs at least a city to contain/control it. bleeba's interesting idea seems to include the notion that shards could be more like the One Ring than they are like Mount Doom. If the given game instance is tuned twoards the One Ring side of a scale, then laying murderous siege to a city might not help much if your goal is to take a small, mobile shard from a rival unit, especially if it is a jewelry-scale focus in the hands of a channeler.

Not that I don't also want to see us able to do some 'proper' siege warfare against Elemental cities.

I like your comparison!   Altough the "one ring" was certainly worth a seige battle.

Now, I always felt that should happen.  Like when I've basically blockaded a city on an island (capturing every other part of the island) and I just don't quite have the man-power to take the last town, but do have the man-power to keep the previous owner away (this happens ALL the time for me in Civ games) I should be able to setup a blockade that does something.  Something that takes food supplies from the town or something like that so that the town starts to die and become sick.  Historically, for the seiges they would hurl dead bodies over the walls of castles to help spread disease and pestilance.  If multi-day seiges don't get into the game, then some stort of over time trouble should come from enemy armies preventing trade in and out of a city. 

That being said, maybe only trade and such can be blockaded, where things like plagues and what have you might be reselved for death channelers or whatever would be appropriate.

I like the idea of fleshing out seiges.  Any enemy army standing adjacent to the outside walls of a walled city should lower or stop food, material, and trade going into the city.  This there seems (by reading some of the descriptions for how materials like metal will be distributed from city to city) a mechanism in place already for a city to store materials and food.  Cities prone to seiges could try to expand these capasity (larger silos?).  It would be cool if cities had the option of building secret project like "secret tunnel out of city" (super project?).  This could negate any penalties to food, materials or trade caused by the seige.  It might also allow armies or heros to secretly leave the castle.  Anyway, I think this would be a fun mega-project to shoot for.  Nothing wrong with a good battle, but seiges do not have to be boring- a bit more thought could make them a real interesting part of the game. 

That sounds awesome, but trying to imagine a player in that situation, I don't think a super project is really feasable then.   Because if you could afford a super project, you could afford just to build army to beat the guys off your walls.

That seems to assume that cities can only produce one thing at a time, which I doubt will be the case for Elemental. GC2 supports 3-part production, and I'm hoping that the tile-based approach to city building in Elemental means that no two cities need be equal in terms of what they can produce.

Some towns might have a huge guild quarter full of armorers, jewelers, provisioners, and distillers while other towns might have the local castle, a scattering of peasant households with a few inns, and maybe a small mage's tower with a few scholars in residence. So if you can have a 'royal' (super/secret) project sponsored by the castle, plus whatever else your additional production tiles might be able to do...dammit, I'm a really greedy player, aren't I?

I do make that assumtion.  Mainly because I don't see much of a separation from MoM, AoW other than you could buiid something in a city, and then build a second thing through a summon spell (so a town Queue and a global Queue).  That being said, HoMM keeps units and building seperate, so it may be that way.   I personally wouldn't be offended if armies and buildings were the same.

My point was just that if a tunnel costs 2000 gold, and a bear rider costs 400... it seems more reasonable that you'd build 5 bear riders.  Or maybe 3 bear riders, a pair of 250 gold archers and a 300 gold tiger rider.

From looking at this screenshot I think it looks like production for buildings and units will be separate:

I think the idea would be (with regards to a special tunnelling project) to get it all in place before you actually came under siege.. say if you had a city that looked strategically/geographically likely to be under threat from a siege, or if a city had narrowly escaped it's ruin in the past due to a siege action.

I actually like the idea of having a tunneling system that can connect your cities at great cost however.(to allow supplies and commerce during a seige.) And this needs its own thread.

If such a thing is implented for balancing reasns shards should not be able to be transported underground.

imagine a fortress locked down on all sides by the forces of evil, actually being a bustling metropolis because it has waygates to a bunch of other worlds. 

I am not really a fan of this other world stuff and these waygates. But thats just me. I myself would prefder that the game have one "universe" so to speak.

Not saying your idea is bad but its a bit too far fetched for me, though I also know that a tunneling system for cities in real life is also not as practical either. But still sounds more plausible than waygates.

Also how do you counter this tactic? With tunnels all you have to do is find the entrance and then tunnel or not their screwed.

Well, that is just how Master of Magic does it.   And as far as I know, its the only game that does it, which is why we need a sequal.  Like its part of the Master of Magic hi-concept, so its not my idea...  its the game idea.  It just hasn't been announced yet.  I'm really not sure how anything could be considered a brain-child of master of magic without at least nodding towards it.   I can't take credit for the idea, I just assume its going to be a thing.

That is a good question.  If you have an underground space (or alternate world) map you could counter it just by camping your army outside the town on the other map.  Alternatly, you could just take advantage of the fact they are shoveling resources to supporting a tunnel to over power the town militarily.  Perhaps spells like tremmor or earthquake would automatically demolish the tunnel (you don't fight an earth channeler by digging tunnels.  Like should be on the first page of the rule book)

I helped with the threadjacking here, but I'd like to see more ideas about how shards should work--especially from folks who might want something other than (or in addition to) the oilfield/coalmine model. If we had a Shard Mobility slider with options ranging from Jewelry to Geographic Feature, would it be a train wreck for the AIs? Would any shard mobility at all just be too much complexity? If not, I still want it.

Threadjacking-I like that term!  Not that I can program my way out of a paper bag, but i think a slider on Shard mobility would be tough for AI.  However it might be able to handle a all or nothing approach (two different behaviors).  Or again, have large unmovealbe shards and also small movable ones (shrads?) that allow some advantage-Maybe three shrads equals a shard.  Anyway, with movable crystals, a good theif, or a magically enhansed hero could preform ledgendary feats (stealing a crystal).  It could shift some power but need not be a game changer.  It would also give reason to fortify your city/fort against thiefs (magical gardians, extra guards, ect).

Fractions without much power could choose to hide the shards in a hidden post or away from the city.  Or maybe in a city.  In this case, the crystal could only be used for defence (perhaps it could be used to make some sort of dome of protection over the area it occupies and adjacent areas).  It would have to be balenced, but this could be used to make a sort of "hidden kingdom" for a limited amount of time for the fraction that owns this (maybe the fog of war is not lifted from this area for enemies and only the strongest of magic users could actually move into this area for say 50 turns).  This hidden kingdom could also have production befifits-creating something like Rivendell or Lorien. The effect would be negated as soon as the crystal is used for anything offensive (help in creating warriors, fireballs, anything).  Once used in offence-the position of the shard would be known to all and all defencive bonuses would be lost.  I also thing this should be limited to one site/fraction.  This would give weaker fractions a way to build strength while preventing the capture of shards from stronger fractions, introduce a neat game option-when to reveal yourself, and again produce a real unique productive city/area that you might hate to see destroyed.  There could be some neat "evil hidden kingdoms" as well.  If this is too hard to code, it might be a nice option for multi-player.