It provides the ability to grind out when you run out of cards, almost giving you an extra card draw each turn, but better, as it's a permanent of your choice from your graveyard, nulling any efforts by your opponent when using removal spells
And wow, are there a bunch available to choose from
While each of these cards is fairly unique in how it breaks the game of Magic, theres one strategy in this vein that actually receives support to this day, and it breaks the game almost as efficiently, even in Commander
When they die, you reveal cards from your deck until you hit a creature, which you slap straight onto the battlefield
If the card in your graveyard is an illegal target as Emergency Weld tries to resolve, Emergency Weld is removed from the stack and you won't create a token
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