I was surprised to see that the wording on Volrath Shapeshifter is not just old card text, but the actual oracle wording. I am curious, why does it not simply copy the the other creature, and have that ability added?
As long as the top card of your graveyard is a creature card, Volrath's Shapeshifter has the full text of that card and has the text "2: Discard a card." (Volrath's Shapeshifter has that card's name, mana cost, color, types, abilities, power, and toughness.)
why isn't it
As long as the top card of your graveyard is a creature card, Volrath's Shapeshifter is a copy of that card except it gains "2: Discard a card."
In fact, I just now noticed that older version of the card DO use the "copy" wording. So there must be a good reason for the change!
Related question, what exactly happens when the top card of the graveyard changes? The wording "As long as the top card of your graveyard is a creature card..." was part of the original Shapeshifter, but it card no longer has that text once it takes the text of another creature. So what rules or text is there in the game that would cause it to change to another creature, or to change back to a 0/1 blue creature?
For example, if you discard Grizzly Bears, then the card on the battlefield is now simply a Grizzly Bears with the discard ability. No where in that card's new text does it say anything about changing to a different creature if the graveyard changes, so how does it work?
The rulings specifically say "A copy of a Volrath's Shapeshifter will have the shapeshifting ability", but why?