They said on live chat that aliens will retain some of the powers even if the pool gene is dilluted by human DNA. I made 4 generations and the first 3 of them had 3 alien childs with all alien abilities and the alien appeareance and the 4th generation had human child with no alien powers at all. Bassicaly there were 3 aliens and 1 human . I was hoping that the human appeareance retain some of the alien powers, i'm dissapointed.

Shimrod said in another thread that the amount of alien DNA required to function as an alien is 20%. You'll just have to refresh the stock by introducing another alien into the bloodline

Or maybe that 20% can be tuned, could take a look at that. Heck, Shimrod may have already done it

Simsvip made a guide and it covers the aliens also

http://simsvip.com/game-guides/sims-3-seasons/

What are the alein abilities?

Abducting your unsuspecting sims and "probing" them without even kissing them first. Hell, I had my teenage female sim getting abducted and "probed" every damn night for 5 nights straight. One time she got dropped off by an elder alien using a cane. Really, an alien with a cane. Damn dirty old aliens.

In addition, controllable aliens can summon meteors and either bio drain or bio boost other sims (transfer their motives to you, or support theirs by draining yours). The meteor will provide one gigantic space rock, a couple of large and several tiny ones. (I always sell the gigantic one, which goes for 2000 or more, and save the rest.) They can eat space rocks to refill brain power (which is a motive which replaces energy). They can GET space rocks via the meteor summons or by stealing them from the science lab at night. They can also recharge brain power as a self-interaction; they sit on a chair or lie on a bed and meditate (it fills up faster than sleeping). They can fix broken objects quickly, using brain power. They can transmute metals and gems: doesn't change the object type, just increases its value (at the cost of brain power). They also have a part time job unique to them at the science lab as Test Subject. And a full-blooded alien comes with high levels in Logic and Handiness; mine had logic 10 and handiness 8, not sure if there's some variation or not.

If you move in a full alien, they come with a UFO which can be used to travel in space (text adventure like the time machine etc), summon storm, and laser attack. Laser attack and space travel both require upgrades, though, and only one can be active. They can also "abduct" any sim they know; they'll take off in their UFO and deliver the sim to their home lot.

Basically the best thing about aliens is that they never have to sleep, particularly if you keep em supplied with space rocks, and have access to easy funds if your sims are running low. It's a well-developed and interesting occult class

Please someone help me I can't find an alien!

How do they summon meteors? Why isn't anybody explaining this? I don't see the option. I got Ambitions, btw.

Their brain power must be almost full to summon the meteor. Just click on the floor [ground level, outdoors] and the option appears.

It seems that they are immune to the death by meteor, too.

Silly me! The alien must be nearby for it to work. It's not like jogging where you go in map view and are able to click anywhere in the world no matter where your sim is. I guess since they are immune there's no harm in trying it out.

I think it also has to be on a lot, not in the world.

My alien lives across the street from an empty residential lot... which is now riddled with craters, lol... since he uses it whenever he runs out of space rocks and/or money

Do you need Ambitions to summon a meteor?

Don't think so!

Actually, you do. Source: http://simsvip.com/game-guides/sims-3-seasons/

oh :O that's too bad