At first I wasn’t go to break this down, but for
once it matters. This is a Trap, and normally
that’s a bad thing… unless the Trap is so potent
as to be a deck focus (like Exchange of the
Spirit is) and is restricted to one per
deck. Then being a Trap is good. Why? Yes,
you have to wait a turn to activate it, but
there is a way to search it from your deck: A
Cat of Ill Omen. It does just that then
places the Trap on the top of your deck (if
Necrovalley is in play, it goes to your hand,
but Necrovalley prevents Exchange of the
Spirit from working). You can also get
Exchange of the Spirit back from the
Graveyard via Mask of Darkness. Spells
have more recursion techniques, as do Monsters,
but at least there is something.
So, what is the game breaking effect?
Exchange of the Spirit swaps both players’
decks with their Graveyards. So whatever is in
your Graveyard becomes you new deck, and your
deck becomes your new Graveyard. Naturally,
that’d be broken entirely on its own, so there
are two requirements. A Life Point cost of
1000, which is usually not a concern, and more
importantly a requirement that you have at least
15 cards in your Graveyard. So now you see the
hard part. If you can quickly get the card in
hand, and get 15 cards in your Graveyard,
without doing that for your opponent, you
can easily make them deck out.
As stated, the difficulty is getting cards into
your graveyard, but not into your opponent’s.
The two easiest methods I can think of would be
Magical Merchant and Fiend Comedian.
The former of course means only Monsters get
sent to the Graveyard and it goes until you hit
a Spell or Trap. The latter might risk
discarding Exchange of Spirits… but as
long as you have recursion handy, it’s probably
worth it: Fiend Comedian has you call a
coin flip: call it right, and you remove the
opponent’s Graveyard from play. Their entire
Graveyard. Call it wrong and you discard a
number of cards from the top of your deck equal
to the number of cards in their Graveyard. As
you can see, both are useful. Now, it’s pure
gain if you haven’t made it past 15 and you
already have Exchange of the Spirit in
hand/on the field (discarding from your deck is
not like drawing from your deck – if you run out
of cards while discarding, you’re still alive).
You probably want some Kycoo and maybe
some Soul Release, because every other
card that combos will tends to make both players
chuck large amounts of cards into their
Graveyard. Serial Spell becomes rather
nice with Soul Release (you won’t turn
out as well with Card Destruction/Serial
Spell since it fills your opponent’s discard
more than yours).
4/5-Here there are a lot more supporting cards
and I believe a very fast depletion deck can be
made with it: possibly a single turn win.
3.75/5-Here it’s primarily for use in its own
deck, which requires a lot of work to make it
flow, but if it does, it’s hard to stop. It can
also be added to certain other decks as sort of
a weakened Fiber Jar.
N/A-It is a promo that was handed out, not in
Hopefully a nice addition to the Yu-Gi-Oh game
in the U.S. Glad it finally got here.