I just finished loading my fort up with a myriad of traps and miles of wiring connecting dozens of pressure plates and switches. I also just defeated the Wall of Flesh and unleashed "the forces of dark and light". Now my fort sees no more enemies. No stray zombies, no flying eyeballs (it was tricky building a trap effective against them, but I did it.) I haven't even had a Goblin army show up in ages. It's boring now, and disappointing. Where did all the enemies go? Will there ever be more?