Magical attack and physical attack are the exact same thing, each meant for a different class(magic attack is useless for FB, for example). We were asking whether attack power or amp contributes more to the damage dealt to monsters. We recommend you to buy the cheap Cabal Alz service from our site.
However amp seems to have no effect or very little effect on damage dealt to monsters, no idea why or if this is a bug. You can measure your damage (cabal alz) simply by testing whether or not you can defeat the scorpion or beetle in Forgotten Ruin in one hit with a level 9 Completer attack. The monster had around 10 to 20% HP left when we removed almost all amp equipment in Cabal, however it still had around 10% HP left after we equipped all amp.
The normal damage is 500, critical damage would be more than 500. But if your attack is not that high, critical damage is also not high. So IMO, you need to balance your items, a combination of amp items and crit items.
For having 50% crit rate, we now compare 200% Crit DMG (cabal gold). And 200% AMP (but with little Crit DMG). The result shows that 200% AMP deals more damage for both critical and non-critical hits. At least most of the cases. Based on my experience, critrate+damage outshines AMP any time. Having a healthy combination of both results in a better overall damage. You can buy alz from our site.