edhseer Commander synergy, explained
Sorcery
Mana cost: {B}
Return target creature card from your graveyard to your hand. Put a +1/+1 counter on up to one target Zombie you control.
on-cast — brings a card back
on-cast — puts a counter on it
Flashback {3}{B}
Causes: a creature leaves a graveyard, put a counter on a Zombie.
Cares about: a creature in a graveyard.
a creature leaves a graveyard — 1,302 cards in the game can cause this (Crawl from the Cellar is one).
When a creature leaves a graveyard thanks to Crawl from the Cellar:
3 other cards care about it too. These are the ones with the most connections.
anything leaves a graveyard — 2,503 cards in the game can cause this (Crawl from the Cellar is one).
When a creature leaves a graveyard thanks to Crawl from the Cellar:
13 other cards care about it too. These are the ones with the most connections.
a creature in a graveyard — 2,769 cards in the game can cause this (Crawl from the Cellar is one).
2,759 other cards care about it too. These are the ones with the most connections.
a sorcery is cast — 3,720 cards in the game can cause this (Crawl from the Cellar is one).
When Crawl from the Cellar is cast:
424 other cards care about it too. These are the ones with the most connections.
anything gets a counter — 4,415 cards in the game can cause this (Crawl from the Cellar is one).
7 other cards care about it too. These are the ones with the most connections.
anything is cast — 31,128 cards in the game can cause this (Crawl from the Cellar is one).
When Crawl from the Cellar is cast:
5 other cards care about it too. These are the ones with the most connections.