Firstly, the masking part shouldn't be too difficult... there's somewhere in the memory that does it and gives the whole 32x32 mask of the tile at that location

The hard part of making the bot, as some had already managed to pick out, is for it to actually find the path. Let's take Matrix's example for instance... its a simple path, but might take ages for a bot to just calculate that short path.

Let's say someone does manage to create some algorithm (probably some alien lifeform) that might allow the bot to find its way around the path... then there are also warp and trigger zones... so on the long run this is hardly possible...

Then if someone can figure out how to calculate the path of where the bot should take, then, well, there are many other limits (not exactly limits, but I couldnt find a better word) in programming which prevents the creation of a bot... *dont have any more examples currently*

So the closest we can come to a JJ2 Bot, as Overlord (i think) has mentioned, is just to "study" a player's movements and stuff for a few minutes and practically mimic it

^^ Wow I didn't realise I've written so much.... lol