Trees of Prophecy
House Rule Collaborative Storytelling
Under the Collaborative Storytelling rule, for the purposes of enhancing role playing, players are basically allowed to make up certain things without having to ask permission.
This includes, but is not limited to: Props NPCs Events
Just ask yourself “would this make sense” before assuming it is there.
For example, if you’re in a bar, it would make sense to have: glasses of alcohol, chairs, tables, bar stools, a sleazy guy in the corner, an out-of-work musician, dim lighting, people arguing, a glass breaking, etc.
Whereas, if you were in a dungeon, it would make sense to have: mud, mold, bones, shadows, some creature wailing in the distance, small puddles of water, rocks, etc.
So, if it would enhance role playing, feel free to take some creative license with the world.
I basically draw the line if the item is going to give you monetary advantage (so, no generating gold, magical items, poisons, drugs, etc.) or fundamentally alter a combat encounter (so, while a shadowy corner in which to hide, a chandelier from which to swing, or small rock you can throw is fine, a cliff / lava flow / tower of precariously-stacked boulders / traps / sudden appearance of allied forces are not).