From what I can see, there are 2 types of strings. About 6 thick, bright ones, and 10-15 or so thin, dark ones. When he flashes, some bright orangish lines also appear near the strings, but they are separate. The movement of the strings seems to be eased or curved, so that they effectively sway like pendulums, slowing as they near the extremity of their movement. This is how I would do it (MFA also attached):
The strings move a bit more briskly in the example than in your video, so you may want to tweak the rotateAmount
values to tone them down a little.
Make sure the cursor is near the centre of the screen when you run the example. I made the character follow the mouse cursor, and neglected to disable destroy object if too far from frame
, so if you move the mouse too far, the strings and/or character will be destroyed.