The primary aim of this mod is to correct as many aspects of the game as possible according to AD&D 2E rules. This affects the NPCs, creatures, items, spells and rules of the game. Engine limitations prevent some of these rules from being implemented, however.
The AI of the entire game will be given a massive overhaul in order to increase the difficulty. Specifically, enemy NPCs use unique scripts instead of a few shared scripts. As the XP cap has been raised, a couple of fights towards the end of the game will be made harder to provide a challenge for the party.
This mod also features new content in addition to changes to the existing game. New spells for wizards and priests, new magical and mundane items, and new creatures are all fully integrated into the game. The enemies you meet will make use of the new spells and items and you should expect to encounter new creatures in the existing areas. Note that while the selection of magical items has increased the amount of magical items has decreased.
Although the quests and the plot of the game remain the same the environment has undergone some changes to prevent metagaming. Expect traps to be relocated, new traps where none were before, magical items to appear in different parts of the game and so forth.
Finally, the mod introduces three new areas to the worldmap. These will contain a number of larger quests, but a few smaller ones will also be available from the existing areas. Similar to the TotSC expansion, these areas can be visited at any time and all the quests are optional.
http://echon.cyg.dk/bgmod-Echon