Though most of the card prices are stayed stable there are still good opportunities for trading. Last times summoner prices went up 2-3x. Looks like there's high demand for summoners. Maybe people want to win tournaments and they need to first level up summoners to use monsters at higher levels. I remember that Tyrus Paladium price was 20 cents but now it's 2-3 time more expensive where it was before. The only card which didn't went up from it's all time low is Silvershield Warrior which is less used card in life team.
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From @smalien