From Nexus Wiki

Columns in the difficulty gda file (difficulty.gda)

This page lists and describes the columns in difficulty.gda for modifying or creating difficulty settings.

Column	Description
ID	Number that is used as unique identifier of the difficulty. For example, for the normal difficulty the identifier is 1, and nightmare is 3
Label	Name of the difficulty setting. Not actually displayed. The displayed text is in STRREF
STRREF	TLK ID for name value e.g. for the normal difficulty it is 371127
descstrref	TLK ID for description text e.g. for the normal difficulty it is 6215916
FRIENDLYFIRE	Multiplier for friendly fire damage. e.g. 0.5 gives 50% friendly fire damage. 2.0 gives 200%. Casual, normal, and hard all have values for this, however in-game those difficulties do not have friendly fire
healthmod	Enemy health modifier. Higher values give higher enemy health.
damagemod	Enemy damage modifier. Higher values cause enemies to do more damage.
attackmod	Enemy attack modifier. Higher values give enemies high attack (chance to hit) values.
regenerationmod	Enemy stamina regeneration modifier.
cooldownmod	Enemy colldown modifier. Lower values give shorter cooldowns after ability usage.
$A3B6334B
$DC6C4EAB
$B0F98CF2	Enemy physical force multiplier. Higher values cause enemies to more frequently knockback/knockdown the player and companions.
ReactiveLimit
TrapDmgScale	Modifies the amount of damage caused by traps
$5B8BE0B6
$06025956
AIAbilityUseMod	Not known for sure. Likely affects the probability of using a skill instead of normal attacks. Only different for nightmare in vanilla DA2 (1 in normal vs. 1.5 for hard. Likely means 50% greater likelihood of using abilities in nightmare)
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$BBD735CA
$BBC129F
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