None of the DW cards need to be banned, although imo, Snoww being at 3 is kinda stupid. If I wanted DW to be hit, I'd ban Morphing Jar / Card Destruction before I hit any of the Dark Worlds. Getting searches, drawing cards, and popping shit all in one card is really, really retarded, while being able to refresh your hand and possibly deplete any useful resources your opponent may have been holding back on.
So Card Destruction and/or Morphing Jar to 0 (probably Jar first due to Empty Jar's existence).