User blog comment:InTheCage/Sphere question/@comment-104.33.41.33-20150219080808

If you are using Shera, her SBB's attack bonus will overwrite angelic foil as they are classified as the same type of buff. Certain leader skills which say xx% attack bonus for 2 turns will also be the same type of buff and will therefore not work with Angelic Foils. Leader skills which say something like 50% boost to attack power when 5 or more elements are present will stack with Angelic Foil as it is a bonus rather than a actual buff. It is better to use Medulla or Legwand gems or other spheres which add stats directly in the stat window as they will stack with buffs. Attack buffs don't directly multiply with BB and SBB modifiers but they do provide some effect so they aren't entirely negligible.

In regards to SBB damage, the buffs in the following order affect SBB damage from greatest to least (Not counting modifiers from other buffs or leader skills):

Element Advantage/Disadvantage, Critical, Spark, Attack Buff