Bug on Necrovalley and the Yubel Contact Fusion "Fantom of Yubel"

[bonweekend]

1. Bug description
   [Describe what the bug is in your own words.]
   So i just had a bug in ranked match while playing Necrovalley.
   This spell card effect make that the monsters in the graveyard of both players cant be moved out of it. They cant be banished, summon, add to the hand or shuffled in the deck. But Fantom of Yubel is a contact fusion that can get special summon without the use of any fusion spell/trap card by shuffling to the deck one “Yubel” and fiend 0 ATK/DEF effect monster from the hand, field or Graveyard. Normally, with Necrovalley on the field, “Fantom of Yubel” shouldnt be able to be summon by shuffling card from the GY, but she can still do it. She can void Necrovalley to summon herself which is a bug.

2. Bug reproduction steps
   The first player activate Necrovalley and end his turn.
   The second simply need to put one Yubel and one Fiend monster with 0 ATK/DEF in the GY.
   Then Fusion Fantom of Yubel by shuffling the 2 monster IN the graveyard to the deck.
   [Write the exact steps to reproduce the bug. Provide a replay code if you can. You can attach replay codes, or use a pastebin link or you can even use a spoiler tag using]

   Spoiler

   your replay code

3. Screenshot OR error code

4. Expected behavior
   [Tell us what should have happened when the bug occurred.]
   Normally, if Necrovalley is on the field, Fantom of Yubel should be summoned only by shuffling the monsters from the hand and/or Field to the deck. Monsters in the GY shouldnt be usable.

5. What OS are you using
   [Windows-10 / Linux / Android]
   Windows-10

[A_Dragon_s_Soul]

This is not a bug, Phantom of Yubel using materials from the GY is not an “effect”, but a cost, therefore Necrovalley does not negate it.

Associated ruling: If Necrovalley’s effect is applying, can I Special Summon Phantom of Yubel? (Q&A #24079) – Card Database (ygoresources.com)