Implement a "world growth" system.

[bbuck]

This would function very similar to the way that World of Warcraft's "phased" zone system works. Players of certain growth states when traveling through an exit would enter a different (but intended to be the same) room. In other words, say you have a forest on fire, and quests that involve dousing the flames. You could have rooms with "fire" objects in them that can be doused and they re-spawn after being doused for other players to complete the quest later, and then once the quest is completed players still run through the forest on fire. This is not conducive to a feeling of "effect" and control on the game.

So we introduce a growth system to the forest. There exists two sets of rooms, one with fire spawns and one without (or just specific rooms if not the entire forest). Initially the player would always enter the initial growth state of the room which contains fire spawns. Upon completing the question, which would advance the players current growth state for those rooms, and then every time the player moves through an exit into those rooms they enter the second growth state of those rooms which lack the fire spawns and can feel as if their work to douse the fires has had a lasting effect on the game world.

Players of groups would have to be forced to enter a specific growth state, I would propose they always enter the lowest growth state of the party, so for solo players that is their growth state and for multiple players who ever has the lowest is the growth state of the party.

This would cause extra work for builders, but also give builders a lot more power when designing quests that effect the world. And from a players perspective, for events that don't need to be extremely lasting (like massive content updates that transform parts of the world) new players can experience "old" content without old players having to see this old content as they play in their "new" world.