Hi, thank you for your reply, but based on the below formula I found here on forum (google translated) , P.attack is a part of the blow damage formula, the higher it is the more damage you do.
" Damage = 70 * (power + pAtk + staticCritDmg) * SS * GDB * mod_per / pDef
power - power Scilla
pAtk - character's physical attack
staticCritDmg - stat bonus to attack point during crit (look in .w near crit multiplier)
SS - if nipples are on = 1.5
GDB (для pve) - Gracia Physical Skill Damage Bonus = 1,10113
GDB (для pvp) - Gracia Physical Skill Damage Bonus = 1,15113
mod_per - modifiers affecting the power of critical attack as a percentage
pDef - physical defense of the target "
Skull dual + 4 - average price 2 - 2.5 KKK P.Attack 445
Icarus dual +11 - average price 5-6 KKK (if you are lucky) P.attack 446
The only positive I find for Dynasty/Icarus is the easier PVP bonus, because if you take the Skull daggers you get the same P.attack and damage and you use the left over 2.5 kkk on adding life stones.