Helps you using WDP in the last moments of SEF to maximize dmg output. Shows a small icon when SEF has 4s left and WDP is up in the next 4s, then follows with a bar at 1.5s left and a glowing effect at 0.4s left.
The number and the bar indicates the time left to 0.4s of SEF where I have to press WDP to make it work. You might have to adjust the numbers regarding your latency and reaction time.