Instead of using possession the alien can control several humans with help of special feature from holographic base. Now we can build mind control farms to catch humans and set their behaviors. Captured persons will help the alien search and pick up useful items or protect him from other aggressive people. So, from now we can do some building work to create mind control farms and then don't be afraid of people that could attack us. The alien may have his own little army, but what may this lead to? Will see.