I would actually advise against unupped precogs. They are not worth it for the heavy cost, and only way you can use it is with two immolations, which means that it will be a dead draw early on. In fact, if you are thinking about utilizing other elements' cards with low cost, use things like fog shield, which are very cost effective and can save you in a pinch (which is actually annoying for me to say, because opponent's fog shield caused my arsenic to miss 4 times in a row in the recent tournament).