An Idea I have been investigating (for a long time) is the use of 'bubble' scenarios, where the quest/missions lead the player(s) to their own section of the map (server bubble) which has other (non-party) players blocked from entering (and interfering). Virtual on-the-fly built terrain (world map huge so the not-seen-by-anyone-else locations can be justified and whatever-is-needed-in-the-bubble can be accommodated). Small enough so 'baking' a custom level isnt overly taxing...
Note - NOT random but some random variations to make elements in the various 'quest' scenarios different much of the time (10 factors each with 4 substitutions = million plus variations...). Auto-generation used with and templated scenario elements (and sets of prop object/opponets viable for the basic quests plot). Solo games could even use this to increase replay particularly with the falling play-thru-hours. Fitting rules logic to place elements properly and nix conflicting details.
Hierarchical templates with parameterized elements to increase variations (but also to inherit and apply 'themes' to make the scenes somewhat cohesive).
For the World Map a kind of influence control map with NPC 'faction' entities which define areas of control (and spawns and local variations of theme flavoring and events). Player's actions kill off spawns (a resource token of the faction entity) which effects that area which a particular faction controls (or multiple factions contend for), thus adjusting the spawns and making them push back or move their influence elsewhere - thus shifting the behaviors and reactions and motives of various NPCs on the map (and what they use their spawned minions for). When a vacuum forms the factions pour in to take that area, potentially conflicting with each other. They attempt to rebuild their token resources, but with different strategies (risky vs conservative, warfare vs economics, power centering vs diffused, etc..)
Thus players can have a visible impact (modifying local influence of the entities), but when they move-on, the factions reassert themselves and 'heal' (adjust) for later players to encounter - the currect placements somewhat differnt than earlier.
MMO with an overall plot and player development pushes them to new areas as they 'progress' ??? Just implement the above stepwise in the progressive zones the players work themselves thru. Each progressive are can have overall themed flavoring (and different factions) following the main plot (ie- the closer you get to The Lonely Mountain the more and more wastelandish the areas get....)
Problem - its alot more complicated than the static stuff MMOs are currently. The logic of the high level influence entities might not be complex, but tuning them so they dont unbalance the whole world suddenly is hard. (GM override needs to be provided for (meaning proper tools to tweak factions) for the inevitable manual adjustments when things do go out of whack).
Programming locations and NPCs be able to operate under the different theme/situational modes (ie- town is in Peace Mode or Warzone Mode or Border Chaos Mode or Depopulated Wasteland Mode and flavors of Faction A B C controlling differently in that local area -- props and NPC demeanor/mix/behavior adjusted appropriately) --- so thats a hell of alot more scripting to make things fit local factors/situations. Alot of the logic can be shared and somewhat generalized, but the endcases explode -- all that having to be developed/tested/fixed/tuned (and largely work in production)
SO what game company wants that expense and risk when they have trained customers to expect nothing better than they already get (or actually degraded from MMOs of 10+ years ago) ??
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