Want to write a tutorial?

[JokeofWeek]

Hmm, couldn't you technically use the formula Dragoon Master uses for his AI, and instead of doing it so it re-calculates every thing every single loop, you could have a base matrix for the map and the tile / tile attributes which would only update when the map changes. And then, just make it so that when the player clicks, it actually calculates the rest of the matrix. I think this would be much faster as it would only have to calculate the players, items and npcs, and it would only calculate when the player clicks. This could actually be used to update Dragoon's code server side too as it could make a base matrix for each map instead of recalculating the same things every single loop for every single map.

Just a few theoretical ideas.