Assuming not much has changed since CBT1:

How much they like a card is very random. Generally you will get +2,+1,-1. It's very random. I've even seen gifts give +3, but generally it feels like your going nowhere.

What stats change depend on the type of card and it's database ID.

Here is a table for how stat gains work:

If you notice, the stat changes are direct inverses of each other.

A full list of gifts can be found here.

The stats listed on the table above will be the girl's stats changed by the gift. The higher their Like and the more Points the card is worth will increase the amount these stats will change. The stats that change will increase and decrease by the same value.

To actually transform, you need 100 Like. The stat that is the highest will determine what transformation will take place.

A more detailed list can be found here.

And Since everyone likes pretty images: (All as one, since apparently your limited to 4 images on this forum.)

From what I've recently read on a Korean Wiki, if you want a wedding dress transform, you need All stats > 200.

This would require you to focus on specifically two stats to increase (Glam/Wis or Pers/Sens) beyond 400 and then switch to the inverse stats till you even out. I'm going to assume this is going to take quite a number of cards, like 200 or more. If you test this, let us know how much it took you.

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