How to understand the rarity of a card?

I got some coins and bought a pack. Its description say that I have the possibility to find a rare and two uncommon. I opened the pack but I was not able to understand the rarity of the cards, what I have to look for?


Card rarity is indicated by the wear and tear on the scroll image itself, the more worn scrolls being more rare.

I've been looking about midway down the left side of a scroll as that seems to have the most distinct markings.

Here's a common:

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An uncommon:

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And a rare:

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