It works, you're just forced to use Gishki Shadow to play this card.
Konami's being effing brilliant, releasing a ritual spell for Nekroz that asks for exact level, when all Nekroz ritual monsters specifically asks you to NOT use exact level.
And then release it as the only Nekroz ritual spell right now in DL.......
It works but you need Nekroz in hand with different levels that adds up to the extra deck monster you sent to the grave. Let's say you sent a level 12 extra monster to the grave, you'd at least 2 Nekroz ritual monsters in hand that add up to 12.
Anoymous
KINGOFGAMES