If a player is attacked and doesnt have any creatures on the field to block with, or any special cards in their hand to defend themselves with, they subtract the attacking creatures power from their life total
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Finally, some bonus info if you're feeling like picking up some extra credit on this area: as long-time players already know, colored expansion symbols weren't always used
Whenever Loki attacks, you can create a tapped and attacking token that's a copy of another Villain you control, only it isn't legendary, it is an Illusion in addition to its other types, and it is sacrificed at the next end step
Only graded cards will sell for those high amounts
Thats partly a reflection of its removal not impressing me, but also how creature-focused White is and just how powerful card advantage stapled to board presence can be