Traditionally, wards are used to protect oneself from damage or harm.
Thus, proc names that end in -ward generally reduce the amount of damage you take from an opponent.
Sometimes those "wards" are defined in terms of the damage that can be done by a particular class of creatures (as in, reducing the amount of damage you can suffer from undead creatures).
At other times, a "ward" can be defined about a particular type of damage (as in, reducing the amount of physical damage any opponent can inflict).
Traditionally, banes are the cause of harm, ruin, or death.
Thus, proc names that end in -bane generally increase the amount of damage you would normally be able to inflict on an opponent.
Sometimes "banes" are defined about the damage you can do to a particular class of creatures (as in, increasing the amount of damage you can inflict on ethereal creatures).
At other times, a "bane" can be defined about a particular type of damage you can muster against any opponent you face (as in, increasing the amount of shadow damage you can inflict on any opponent).
Traditionally, curses are the cause of harm or punishment.
To differentiate curses from banes: banes increase an opponent's damage, but curses decrease the opponent's health or strength (their amount of blood for example.
Thus, proc names that end in -curse generally make an opponent more vulnerable to damage.
"Curses" are sometimes defined about the type of damage an opponent will be more vulnerable to (as in, reducing opponent's resistance to holy damage, which means that every holy damage that you inflict will do more damage than normal).
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