Originally Posted by
Gludateton
That's actually normal, let's assume that you have decent weapon grid (130% assault +30% ele), elemental advantage and using friend's 100% eidolon.
Multiplier for 45% ele eido: 2.3 (130% grid) * 3.2 (100% eido + 45% eido + 45% advantage + 30% weapon) = 7.36x
Multiplier for 40% char ATK / 20% HP: 2.7 (130% grid + 40% eido) * 2.75 (100% eido + 45% advantage + 30% weapon) = 7.425x
So in this case not only you get higher damage, but additional HP (I assumed event eidos here, but general idea applies to gacha's too).