The topmost row with the arrows are not part of the combat, it just shows what the opponent will play on his *next* turn.
Creatures attack at the end of your turn. If there is a card in front of them, they will deal damage to that, otherwise they will deal damage to the opponent.
Two flying creatures don't block each other.
In the Campfire, 'feed' them a poisonous animal to get multiple upgrades.
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