All "Gravekeeper's" monsters gain 500 ATK and DEF. Cards in either player's Graveyard cannot be banished. Negate any card effect that would move a card in the Graveyard, other than itself, to a different place.
Stop throwing wrong informations.
Necrovalley never banned in OCG or TCG, actually Konami errata it so it's became stronger in OCG.
Also, many GK Cards mention this field card and Ishatar uses it so it's just a matter of time until we get this card (I believe they will release it in Card Trader and not a reward)
It says "Negate card effects that move a card from the graveyard, other than itself, to a different place"
Phoenix moves itself out of the graveyard. Hence it can resummon itself easy and destroy Necrovalley.