Many of the cards seem powerful enough to break into eternal formats, as well as the potential to shake up the current Standard meta significantly
Exdeath, Void Warlock's last ability checks your graveyard at the moment it would trigger to see if you have six or more permanent cards in your graveyard
He fights up to one target creature an opponent controls
Dig Through Time This is a Delve-powered card selection, and clearly one of the best blue cards MTG has ever designed for finding exactly what you need
In this MTG version, you have to contend with the five mana cost for playing this card, so it'll be hard to find room to cast it unless things are going very well for you, in which case your opponent can concede in response
If you don't control four or more artifacts at that time, the ability won't resolve and none of its effects will happen