The fact that US Playing Card Company is now printing a rainbow of colorways on their classic Rider back design means that the climax phase of many packet tricks can now be even more impressive.  For some reason (no doubt understood by experts of human psychology), when four blue back cards change to four different back colors, it's more magical and stunning than if the blue cards simply change to four red-backed cards.  The work is no different, but the magic seems to be more amazing. 

This packet effect is a version of the Twisting the Aces plot with the color changing back climax, similar to the famous Bac-Flips effect, but for the big finish, the card backs change to pink, orange, green and light blue.  It looks great! 

The effect:  four of a kind are shown in a faceup fan.  One at a time, each of the four suits turns facedown (each showing its blue back in the process).  Then after the fourth card has turned facedown and back to faceup, the four cards are shown to have RED backs.  Then for a jaw-dropping climax, the four cards are shown again, and each card has a completely different color back. 

The four colored back cards are ungimmicked and so they can be handed out for examination -- a simple ditch of a gimmick is needed, but the focus is on the rainbow backs, so you will have plenty of misdirection for this.

The value of the cards (for example, Ten, Two, Seven, etc) is different in each set, so no guarantee of what value you will get, but the face value is not important in this color changing backs effect.    By the way, this trick is not very hard to do, so every magician with less than four thumbs can do it.