Attack
An attack is one of the most basic ways to damage a monster in PSO.
Types of attacks
Normal attack
A 
normal attack deals damage equivalent to [(ATP - DFP)/5] x 0.9. In-depth ATP calculation can be found on the game mechanics page.
Heavy attack
A 
heavy attack deals 1.89x the damage of a normal attack and has 0.7x the accuracy of a normal attack. A heavy attack will push back an enemy hit by it, with some exceptions (e.g. Ob Lily).
Special attack
A 
special attack has 0.5x the accuracy of a normal attack, doesn't fill the Photon Blast gauge, and doesn't push enemies back. These properites doesn't apply to 
Vjaya, Dark Flow, 
Dark Meteor, Frozen Shooter, and Snow Queen, whose special attacks have 0.7x the accuracy of a normal attack, do fill the Photon Blast gauge, and can push enemies back, similar to a heavy attack.
A sacrificial special attack – Charge, Spirit, or Berserk – deals 3.32x the damage of a normal attack. Vjaya's special attack deals 5.67x the damage of a normal attack.
A melee attack whose special fails to activate deals 0.56x the damage of a normal attack.
Gush, Geist, King's, Blizzard, Arrest, and Chaos-series weapons deal 0.67x the damage of a normal attack.
Attack combos
Almost any weapon can attack in a three-hit timed combo; for weapons that cannot, see the list of weapons which cannot combo. The first attack of a combo has no accuracy modifier, the second has a 1.3x accuracy modifier, and the third has a 1.69x accuracy modifier.
