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Damage
Damage refers to the amount of HP removed from the recipient of an action. Damage is determined through the multiplication and flooring of several terms. Every variety of damage begins with a Base Damage term. Thereafter, Base Damage multiplies with a series of terms until a resulting numeric value is reached. This resultant damage is the only numeric value the player sees when inflicting damage.
Calculating Damage
Calculate the value of each term. Different equations have different terms, so be sure that you're using the correct equation. After calculating the value of each term, begin multiplying the terms starting with the Base Damage term. After multiplying two terms, floor the resulting damage.
Example:
 1. Calculate the term values (Numbers seen here are arbitrary)
 Base Damage = 100 + 53 + 3 = 156
 Class term = 1  0.64 = 0.36
 2. Multiply terms
 (Base Damage) × (Class Term) = ???
 156 × 0.36 = 56.16
 3. Floor the result
 Floor (56.16) = 56
 4. Repeat by multiplying the result with the next term
Using BGWiki Damage Equations
When reading the page, the order of calculation begins with top term listed. For instance:
 Base Damage
 Class Term
 Type Term
Equals
(Base Damage) × (Class Term) × (Type Term)