It's funny, because this picture makes you realize how the alien from the series really isn't that well detailed in himself. Anyone who doesn't understand this reference knows nothing of pop culture. Anyway, the weird thing was that this really wasn't that much of a detailed picture. It's just that it has so much more depth the actual alien from the game. It's funny to imagine some of those xenomorphs using a gun, especially a silly looking one like that. I like how you have the alien in the background on the tank.
Green is a pretty standard color for a T-shirt. It certainly seems like the kind of design you would want from something like this. It's funny to see the little antennae coming out of this big alien's head. You did a pretty job with shading too. That's something artists should always remember.