Two types of invasion (The alpha and the delta spit in two episodes) with 10 maps each... really awesome! You can spend hours playing this... really cool to play with different type of wads, especially weapons. Not made by me. It was made by Zalewa, credits go to him and anybody who helped... Enjoy!
One of the best Doom II mods ive ever seen man! Play this together with weapons mods, and you can spend an entire day playing this =D