The city

Xanthar and his crew landed in a secluded area just outside a big city. Their advanced stealth technology made their ship turn invisible from both human eyes and current human technology. They figured they would be safe from sight at least for a time. Off in the distance, the city lights were seen illuminating the dark concrete jungle.

The automated scan revealed the relatively high population density of the city, even during nighttime like this. It also showed that the city had places like empty abandoned buildings and neighborhood and the extensive sewer system, all of which were viable place for temporary base.

There were also secluded backalleys and the city parks which were suitable for ambushing unsuspecting females.

Xanthar started another more detailed scan on nearby buildings and surrounding area to determine their potential targets. A couple minutes later the result came.

The streets were mostly empty, save for a few shabbily dressed males, most of them seemed to have high concentration of ethanol or psychoactive chemicals in their body. There were also a few lone females walking on the street and some females with skimpy clothes just hanging out on the streets.

There was a neighborhood nearby. Many of its inhabitants were already asleep although many were still awake. Maybe not the best place to snatch humans in low profile since the population density was quite high, and alarm systems and firearms were detected in the houses. Those alarms can be deactivated, but they require time, a little bit of resource, and actually sending one alien to hack into the security system of individual houses. And one missing family member in their own house would cause an uproar. So it's more risky.

The large building nearby was an office building, which still had some humans working in it. It also had some alarm system and a couple security personnel at the ground floor. Same as the above, the security system must be disarmed and now it had guards that must be either tricked or incapacitated. But this one was probably more rewarding. And less dangerous too, since the scanners don't detect any amount of combat-ready firearms.

An even larger building next to it was a mall. It had even more security guards and lots of security cameras. It was mostly empty now, but at the day this place was often crowded. Now, snatching people in a crowd during broad daylight might not be a good idea, but in human minds, people missing while at mall felt less suspicious than people disappearing in their own house. Especially considering the amounts of camera blind spots and potential ambush spots this mall had.

And finally, there was a building called a gym, which was a place for humans to do physical exertions to train their body. There were quite a few females still in there, either still exercising or just finished exercising. This was an attractive target, because the aliens for some reason really love the scent and the sweat of female humans.

Now for the strategy. It's best to ambush one target at a time and when she was alone. Even better if she was in a condition where she was distracted, exposed and ****. But when is it and where does it usually happen? Maybe a biometric scan could help. Biometric scan described physiological and mental condition of the targets in detail. Xanthar decided to use it later when they were in proximity of the target. Ambushing more than one targets at once was viable, but more risky and needed a bit more work.

The aliens' stealth technology made them capable of doing low profile operation completely unnoticed. Xanthar and his team activated it and started heading to the city.