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They might count them ([mtg_card]Cranial Plating[/mtg_card], or the Affinity and Metalcraft mechanics), make them easier to cast ([mtg_card]Renowned Weaponsmith[/mtg_card]), find them for you ([mtg_card]Trinket Mage[/mtg_card], [mtg_card]Treasure Mage[/mtg_card], [mtg_card]Sanctum Gargoyle[/mtg_card]), reward you when you cast them ([mtg_card]Riddlesmith[/mtg_card]), or reward you when you break them ([mtg_card]Disciple of the Vault[/mtg_card])
However, that was printed in a McDonald's pack as a rare and not in any core set
However, certain categories of cards are so important, so powerful, and so recognizable, that even a fundamental strategy guide would be incomplete without mentioning them
Key Colors: Any
Q: What are the point values for the Public Events