It was created with Unique Shell pattern, combined with drop stitches as ruffles.

Knit
Purl
Yarn over
K1 with 3 wraps- insert right needle into the stitch knitwise, wrap needle with yarn 3 times, pull the 3 wraps through the stitch to form a stitch with 3 wraps.
K1 & drop wraps- knit 1 stitch and drop/unravel all extra wraps