KSD is an opener that uses T-spin single in the first bag, requiring only 2 rotations to complete the first bag. Second bag results in a T-spin Double. There are 3 piece dependencies(L before S, I before Z and O before J) to execute KSD. Despite that, the speed at which KSD can be built compensates for the piece dependencies. This opener was originally created to counter PC loopers. I would recommend learning this opener for fun.

First Bag

Three requirements: O before J, L before S and I before Z. The rotations needed are T and J only.