Color difference in creature level boxes in battle areana


Does anyone know if there is any significance to they gray and blue colors in the level boxes for each of your creatures when in battle areana?


Grey = common
Blue = rare
Yellow = epic
Red = legendary
Green = unique


Gotcha, I was thinking it was an indicator Like blue meant they didn’t have that creature on their team and gray meant it did. Guess I probably would have figured it out when I finally get an epic! Would of realized seeing the yellow.