The game now has a 3D audio effects engine which includes positional stereo, distance attenuation, distance delay, and occlusion of higher frequencies based on physical obstruction. You will notice that sounds are more muffled when the paths that sound waves must travel between the source and listener are more constricted.

The monsters now have audible footsteps, and with the audio effects engine, you can tell where they are coming from without seeing them. You can even hear whether or not there is a barrier between you and them because of the change in frequency.

I am currently in the middle of creating tactical behavior for the monsters, including their ability to throw projectile attacks at the player. Their pathfinding algorithm is going to be augmented into something more efficient and flexible.