I was playing Clash Royale and wondered if all the cards were the standard or is that just the maximum level they can be. Please help me.
Well, there is a Tournament level Limitation, but it depends on the kind of the Tournament how it is treated!
First of all the Limitation is that the Towers and the king Tower are limited to level 9.
The same level is the Limitation for Common Cards.
Rare Cards are Always Limited to level 7 and Epic cards are during that Battles maximum level 4. Legendary Cards are always level 1.
Exception!: If someone uses a mirror on level 4, the mirrored cards are going to be 1 level above that limit!
Well, in Friendly Battles, the Cards are always exactly Leveled Like mentioned above.
In Challenges And Custom Tournaments Cards are played the Level that you got it but if you got them higher leveled than the Limitation then they are during battles exactly that levels Mentioned above.
In Draft/ Special challenges where you can play ALL The cards, they are treated like in Friendly Battles.
In Special Challenges Where you can play with your decks the same way as in Classic/ Grand Chanllenge (e.g. the first Double elixir Challenge).
I Hope I could help you and I Hope I didn't explain it too complicated.
The rarity of cards does not matter . King tower, princess towers and all cards are capped at level 9 in friendly battles and in events and tournaments. I don't have any card of level 9 so I don't know if they have a higher level or not all my cards are 6-7 and a level 8 witch. However I have heard rumors that some cards have a higher level than 9 but I personally don't support it unless I check it myself.
As EBongo answered the card can't go above the max level as in the tournament rules and the cards certainly do not level up to the max or tournament max level. Though in a recent update in friendly battles(ONLY IN FRIENDLY BATTLES!) cards are leveled up to tournament level if they are less than that.