Oversold Cemetery
Enchantment
At the beginning of your upkeep, if you have four or more creature cards in your graveyard, you may return target creature card from your graveyard to your hand.
"'Get out! Get out!' the dead screamed. 'We've not room for one more! Get out!'" —*Hexes of Dunbarrow*
Illustrated by
Wilds of Eldraine: Enchanting Tales#33RareEnglishLegality
Rulings
Oct 4, 2004
The check for four or more creature cards is performed on resolution as well as at the beginning of upkeep. So the trigger may not do anything if there are not enough creatures any longer.