Here, I look for cards that specifically target enchantments (or artifacts/enchantments), and usually one at a time
Up to four copies of a unique Pokmon card can be in your collection in total (so if you already have three, only one will be transferred), and just one copy of each ACE SPEC, Prism Star, Pokmon Star or part of a V-UNION card
For example, I have a Scion of the Ur-Dragon deck that can kill people in around three turns, its a blast to play, but one I rarely use as its a little higher on the power scale than anything my friends build
As far as bringing cards in, Lithomantic Barrage, Get Lost, and Destroy Evil are all good answers to big creatures that try to roadblock your attacks
Like I said, its by far the most powerful thing you could be doing in Standard these days, so good players are going to play it