User blog comment:Beboper/Ultra Rare Price Guide Update/@comment-68.38.162.145-20121201225611/@comment-5428123-20121202041744

Usually, traders in the market place judge the price of cards based on card value rather than in pure potions. The problem with using pure prices only is that pure prices tend to vary significantly compared to card value. Because of this, card value and pure prices do not always correlate well with each other.

Also, the point of the guides is to report prices as seen in the market place, not to manipulate or control the prices in any direct way.

As well, it should be noted that the value of potions isn't fixed, but fluctuates based on current events taking place. There are times when energy drinks are worth more, and times when power potions are worth more.