This glitch will put any amount of packs as 150 DP. Here's how to do it:

1. Go into whatever set, and checkmark 1 pack.

2. Select the set you want to buy all, or some of, and press L. Or checkmark them manually.

3. Exit out of that set, and highlight another set (Do NOT go into the other set) Now press R.

4. After doing all 3 above, Press X.

If done correctly, the packs you wanted, plus the one you checkmarked earlier, are only worth 150 DP altogether. This can be done with any pack.

Note: The set must not be empty in order for this to work.