I'm no judge, but I believe that this situation would be similar to when you have creatures put into play tapped and attacking against a ghostly prison. In this case, the restriction occurs in the declare attackers step. Essentially, the creatures are prevented from attacking unless a certain condition is met. However, this does not prevent creatures put into play subsequently (via Hero of Bladehold or Geist of Saint Traft for example). I am fairly certain that your case works the same way. The restriction prevents it from being declared as an attacker but does not remove it from combat if it somehow enters the battlefield attacking.
Please avoid phrases like "I believe" when answering rules questions. This gives the impression that you're not sure of the answer yourself. ~ Hendrik
Medomai couldn't have attacked (aka, be declared as an attacker), but it never did attack, it just entered the battlefield already attacking (so was never declared as an attacker).
Attacking restrictions keep creatures from being declared as attackers- this is checked during the declare attackers action in the declare attackers step. A creature that enters the battlefield attacking gets around said restrictions because they aren't checked when a creature enters the battlefield attacking.
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Currently 62/265 cards.
Please avoid phrases like "I believe" when answering rules questions. This gives the impression that you're not sure of the answer yourself. ~ Hendrik
My decks:
-Modern UWR gifts control
-Modern Mono-G aggro elves
-Azami, Lady of Scrolls EDH
-Glissa the Traitor EDH
-Modern UWR Counterbalance Control
-Modern UW enchantment control: primer, on tapped out
-Modern regular UWR control
Attacking restrictions keep creatures from being declared as attackers- this is checked during the declare attackers action in the declare attackers step. A creature that enters the battlefield attacking gets around said restrictions because they aren't checked when a creature enters the battlefield attacking.
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