The Meathook Massacre

I have a [[The Meathook Massacre]] on bf, I cast a second one and it enters.
I choose to put in the gy the one that just entered. The triggered ability that shrinks P/T fires but when it resolves it does nothing.
Apparently, during resolution, the ability checks the presence of the one card that generated it.
I don't think that should be the case.

Start by reproducing the two-copy The Meathook Massacre interaction described in the issue, including putting the newly entered copy into the graveyard. Trace the triggered power/toughness-shrinking ability through resolution and verify that it still applies when the generating card is no longer present; done means the interaction matches the card's intended behavior.

Written by the indexing model from the issue text.