Nooooo.... They have traits. Stats and abilities of both... I have done it. I have them. Lol they are aliens and can do alien abilities and KEEP THEM because since that post I aged my teen to young adult. She has the stat bar, gem, spellbook, spell perks and all Just like a 100% spellcaster. Of coarse you cant make one in creation, but wheres the fun in that? They wanted to know if there was a way to make a spellcaster alien. And there is. Point blank. She not only has stats of spellcaster AND can overheat AND can cast and learn spells but she has all the alien interactions as well..not to mention a downfall to not being able use a disguise(unless you want your sim to be random all the time switching back and forth) when they meet new sims they react to them as ALIENS. So realize I have done this and I KNOW it works. The game recognizes them as ALIEN and SPELLCASTER. I posted a pick of Demi Galaxy (my hybrid) says "known alien" and "neophyte" so how does the game and characters not recognize them as aliens? And what do you mean by loose traits? Cause they def dont. Lol they ONLY downfall is the hybrids CAN go into disguise but being there is no option to edit it they randomize. But other than that. That is the only way to make an alien spellcaster. Lol