đồ up từ 3* lên 4* cực hiếm nhé, bên JP ko farm ko mua dc từ cash shop, ai chơi lâu dài thì chưa nên up lên 4*
"Keep them, way too valuable, until you're very sure the 3* you want to augment to 4* is that good.
In the JP version, the rainbow bulb (used to augment 4* to 5*) is very common, but...