I wish they implemented the season end rewards after the season ends... I had rented cards using my hard earned DEC to at least reach bronze I, only for the cards to be taken back again few hours before the season ends because of high demand of rental cards that time, thus dropping me to bronze III... and as if that was not enough bad luck... the rngesus gave me 4 potions and 10 DEC as a reward for the end of the season...
Oh well... there's not much I can do about it so I'll just have to play more I guess.