Ai Features:
Normal Aliens
-Intelligent Alien Entities
-Accurate Shooting Skills
-Easy to kill, Easy for them to kill you also (realistic)
-Challenging
-Random spawn area
-Can duck walk, hide, strafe
Boss Alien
-Super Hard to Kill
-Have different weapon
-Can act the same as normal Aliens
-Fast
-Can dodge bullets
Items Features
-Health kits
-Guns and rifles have no cross-hair but can aim (realistic effect)
-Convertible rifles from simple fire to grenade launcher
-Melee attack of weapons
-Spawning weapons and bullets (secret areas)
-Portals
Player Features
-Can duck, hide, dodge, fire, melee attack, strafe from left to right
-Can aim
-Can pick up weapon
-Fast
-Can interact
Map
-Large maps
-Some are puzzle maps
-With different challenging levels
-Realistic environment (except inside alien base)
-Autosave