Quote Originally Posted by douglas View Post
More specifically, Teleportation Circle. No other means of teleportation I am aware of has enough capacity to have the effects described here without assuming a truly staggering number of high level casters.

How would the Tippyverse change if that single spell were removed? There'd still be the possibility of a trap-based economy, but it seems like much of the military and trade underpinnings of TV would fall apart without TC.
You aren't really likely to see a trap based economy without the population concentrations that become a necessity when TC's exist. The initial cost is quite high unless you are using Wish abuse and the like to get the traps cheap. The TC's almost make a viable market for traps that are turning out things like 14,400 backpacks per day. A hundred cities with an average population of 10 million each? All reachable essentially by walking? The item traps aren't going to be flooding the market in the Tippyverse. But when you are lucky to have one city a nation that breaks a hundred thousand people?

Edit: And ninja-answered. Still leaves the question of what you think D&D magic minus Teleportation Circle would logically do to a setting.
Without Teleportation Circles you can't drop armies into enemy cities, without that ability it actually becomes viable to defend your borders in a more traditional way. Sure, you can use various methods to teleport your army in (run them through a Shapechange trap and have them turn into Archons and teleport in to attack) but all of those methods have draw backs that TC doesn't.

As for what such a setting would be like? I don't really know, I've never really thought about it before.