I was just wondering if I decide to play with the yellow or red aliens, do I choose randomly from all 50 aliens or just the yellow or red pile? Is there any rule? How do you play it?

Is it possible to play with different colored aliens? Are they balanced or I shouldn't mix green with red for example?

You can mix and match colors as you want. It is only a suggestion that new players learn with green aliens then move up to yellow. Once you feel comfortable enough to add in red, you should be playing with all 50 aliens. Of course, you are free to do as you please. If you want a more complicated game, you could try dealing out only red aliens. Never done it myself. It's most fun to play with all of them since you have more possibilities that way, and that's the way the game is intended to be played.

ok. well in regards to you question. My cousins and I play with some "house rules". but thats another story.

With dealing out Aliens. I see how many people are playing and the deal using only the red light powers first. so that everyone will get a Red to try to make it a bit fair. then usually deal 5 more flare cards to each player with all of the cards. so each player will get one (or more depending on the amount of people playing) red powers and the five of the rest. they then choose their power and pick a flare to add to the deck. (if you play with that varient.)

House rules should of course prevail, so there's no problem with your method; however, the reasoning is a bit off. "Red" aliens are not better aliens. They are simply not meant for newcomers because they either have complicated powers, require a deep knowledge of the game, or may not present an obvious strategic worth. Once you are experienced enough to feel comfortable with any level alien, you should be as good with "Green" aliens as "Red" aliens. In fact, the most common alien to win in the games I've played so far (probably over twenty games) has been Loser, a "Green" alien. It's not unfair to deal someone all green aliens and another player all red, if that is how the shuffle chances to be.

But like I said, if you particularly enjoy "Red" aliens, by all means use your house rule! Just clarifying the reasoning for others, mostly.

Our first few games we only played with green. After we became comfortable with the game mechanics we mixed them all together. I did not find that all the reds are stronger than yellow and green. Except for the Virus

It's occurring to me that the coours should have been isplayed on the flare not the aliens. It's the flres we use to choose the aliens. I reduce the grade of iven this version to A++++++++++++++++++++++++++++++-

The colours are on the flares; it's on the right side of the card next to the alien's name.