Idea using lots of sequence
An idea to do that is to make a variable that is called duration and when you run the custom command do a sequence, the first thing you want to do is to set duration to 0.2 (or whatever you want it to be), then you want to run a branch, if true then divide duration by 2, if false, do none. and finnally the third thing you want to do is to is run the delay with a duration of the variable duration.
