I have a suggestion for <Damage Filter: Outgoing> <condition> <damage>:

A damage condition that checks to see how much damage (within a certain time frame if possible) is dealt to either the victim or the attacker and continuously adds up the damage dealt until it hits a variable "total damage" cap OR the set time frame runs out, which the former passes the condition once enough damage is dealt and the action is executed, and the latter does not pass the condition and the action is therefor not executed.
The time frame could be toggled so that damage will be added up indefinitely until it hits the total damage cap.
Once the total damage cap is reached, the action can be executed, and the damage counter will be reset back to 0, to either reach the damage cap again or disabled once it has reached the counter, with a set amount of times it can reach the damage cap multiple times before disabling.

To summarize:

Total Damage within a variable amount of time in seconds
(e.x., Total Damage that must be reached to execute action = 100)
(Time in seconds for Total Damage to be reached = 5 seconds)

If the timer runs out before the damage dealt can reached, the condition will be failed and the action will not be executed, resulting in the timer and damage counter resetting back to their original values or disabling entirely.

The timer itself can be disabled, and allow for damage to add up forever until the Total Damage is reached.