As far as changes to make to the budget build of the deck, I wouldn't change a single card
(Although be warned: the median value is only $1.25, so this average value is driven up by a small number of expensive rares, and many individual packs of Double Masters will hold two bulk-level rares.) With 42 rares in the typical box, this adds another $133 to the expected value of a box, which means the rares and mythics alone currently add a total of $267 to the value of a Double Masters booster box
In order to make sure you know where you can find these incredible cards for yourself, lets review what we know about obtaining these LOTR Box Topper cards
Take a look at some previews including: Kozilek, Butcher of Truth, Wrenn and Six, and Lilliana, the Last Hope
Myrkul, Lord of Bones Myrkul, Lord of Bones offers a commander interested in doing much more than just sacrificing creatures