Butterfly stitch is a pretty knitting stitch. The reverse looks interesting too. Knitted in a multiple of 10 + 9 sts and 20-row repeat.

Knitted in a multiple of 10 + 9 sts and a 20-row repeat.
Rows 1, 3, 5, 7 - RS: K2, * sl 5 wyif, k5; rep from * to last 7 sts, sl 5 wyif, k2.
Row 2 and all wrong rows: Pur all sts.
Row 9: K4, * k1 uls, k9; rep from * to last 5 sts, k1 uls, k4.
Rows 11, 13, 15, 17: K7, * sl 5 wyif, k5; rep from * to last 2 sts, k2.
Row 19: K9, * k1 uls, k9; rep from * to end.
Row 20: Purl all sts.

Knitting abbreviations:
K: Knit | P: Purl.
Sl: Slip stitch purlwise | Wyif: With yarn in front.
K1 uls: Knit 1 under loose strands. (Insert RH needle through the 4 strands from below, then knit next stitch bringing the knit stitch through the loops)