Dynamic HUD suggestion: A "rapid succession" perk icon.

[RI-IY5]

There's a cool-down icon for some perks, letting you know how long before they can be reactivated, or how long their affect will last for.

There's also perks with a "rapid succession" requirement, to kill X enemies in a short time.
I'm unfamiliar what the timing requirement for a "rapid succession", do you:
A) Need to get a kill every second to maintain that "succession", or
B) Need a "rapid" number of kills over a set period (e.g. if the time is a 10 second period and you get 9 kills in the first three seconds, then you have another 7 seconds to get that last kill).

Unless you're kill counting, this can be difficult to keep track of how close you are to activating these perks. Which can be difficult when in the thick of combat, and using multiple weapons (if the perk has specific kill requirements).

Perhaps an indicator that builds up as you get valid kills, but deteriorates in the lull between kills would be a good idea.
Then once the perk activates, it can remain as the cool-down indicator (for those with a cool-down).

[Chicken Tsunami]

Bump. We need answers for this as it is critical for multiple perks.

[The4Winds]

late reply but I completely agree to either your solution or clearer text from the devs