Talk:Items/@comment-77.225.76.60-20180918152916/@comment-26447088-20180920001506

You can use 4 crystals to evolve an 8 star instead of using another copy of the same 8 star. For example, if you have and wanted to evolve an Aterui (Spirit) base, you could use 4 Null Crystals (because she's the Null element) and she'd go up to +1. You can use another 4 crystals to evolve that +1 up to +2. They do this because the 8 star rates are low, so this way you only need to pull a base then collect crystals from event rewards in order to evolve it.

Bouquets, cakes, and stuffed animals are used on 8 stars to increase their friendship level, which unlocks new homepage quotes when you have them set as your leader. This is purely aesthetic and doesn't actually affect their stats or anything.