It should be known that gold had the ability to repel magic to a certain extent.
This meant that although the market price for each gold coin was a hundred silvers, nobody in their right mind would ever give up a gold coin for that kind of exchange.
In a certain sense, gold coins could be considered a premium currency that only the truly rich dealt with.
That was why the association even offered that as a reward in the first place. In fact, it was one of their more popular rewards.
As such, Apollo looked over a fairly large opportunity when he glossed over both the hundred gold coins and five hundred gold coins.
However, once he saw the words, 'Eye of an Adult Unicorn', a bit of surprise appeared on his face.
He could vaguely recall that he was taught about unicorns back at his school. However, not even they really knew anything about them.
Frankly, that lesson left an impression on him simply because of how random and vague it was.
Stop it One Punch Man!