With A, ch 2.
Round 1 (RS): Work 6 sc in 2nd ch from hook—6 sc. Place marker for beginning of round. Move marker up as work progresses.
Round 2: Work 2 sc in each sc around—12 sc.
Round 3: [Sc in next sc, 2 sc in next sc] 6 times—18 sc.
Round 4: [Sc in next 2 sc, 2 sc in next sc] 6 times—24 sc.
Round 5: [Sc in next 3 sc, 2 sc in next sc] 6 times—30 sc.
Round 6: [Sc in next 4 sc, 2 sc in next sc] 6 times—36 sc.
Round 7: [Sc in next 5 sc, 2 sc in next sc] 6 times—42 sc.
Round 8: [Sc in next 6 sc, 2 sc in next sc] 6 times—48 sc.
Round 9: [Sc in next 7 sc, 2 sc in next sc] 6 times—54 sc.
Round 10: [Sc in next 8 sc, 2 sc in next sc] 6 times—60 sc.
Round 11: [Sc in next 9 sc, 2 sc in next sc] 6 times—66 sc.
Sizes Child (Youth/Teen) only: [Sc in next 10 sc, 2 sc in next sc] 6 times—72 sc.
Size Youth/Teen only: [Sc in next 11 sc, 2 sc in next sc] 6 times—78 sc.
All sizes: [Sc in next 32 (35, 38), 2 sc in next sc] twice—68 (74, 80) sc.
Next Round: Sc in each sc around.
Repeat last round until hat measures 6 1/2 (7 1/2, 8)"/16.5 (19, 20.5)cm from beginning.
Place a marker, in last round of hat, at center back. Note: The exact location of the back of hat doesn't matter. Select a location you would like to be less visible (since it will be at the back of the hat).
Join A with sl st in 12th (13th, 13th) sc following the marker, to work away from the marker.
Row 1: Ch 1, sc in same sc as join, sc in next 9 (11, 13) sc, turn—10 (12, 14) sc.
Row 2: Ch 1, sc in each sc across, turn.
Row 3: Ch 1, sc2tog, sc in each sc across to last 2 sc, sc2tog, turn—8 (10, 12) sc.
Repeat last 2 rows until 2 sc remain.
Last Row: Ch 1, sc2tog—1 sc.
Fasten off. Join A with sl st in 12th (13th, 13th) sc before the marker, to work away from the marker, and work second earflap same as first.
Edging: With RS facing, join A with sl st in edge of hat, work rev sc evenly spaced all the way around edges of hat and earflaps. Fasten off.
With B, ch 7.
Row 1: Sc in 2nd ch from hook and in each remaining ch across, turn—6 sc.
Rows 2–6: 2 sc in first sc, sc in each sc across to last sc, 2 sc in last sc, turn—16 sc at the end of Row 6.
Rows 7 and 8: Ch 1, sc in each sc across, turn.
Row 9: Ch 1, sc2tog, sc in each sc across to last 2 sc, sc2tog, turn—14 sc.
Rows 10–12: Repeat Rows 7–9—12 sc at the end of Row 12.
Row 13: Ch 1, sk first sc, sc2tog, sc in each sc across to last 3 sc, sk next sc, sc2tog, turn—8 sc.
Rows 14 and 15: Repeat Row 9 twice—4 sc.
Row 16: Ch 1, sc in each sc across.
Embroider: With yarn needle and A, embroider eyes, mouth and teeth in cross-stitch as shown in chart. Work each cross stitch over one sc, and each straight stitch over 2 rows.
With A, ch 41 (47, 51).
Row 1: Sc in 2nd ch from hook and in each remaining ch across, turn—40 (46, 50) sc.
Rows 2 and 3: Ch 1, sc in each sc across, turn.
Fringe: Cut approximately 120 (138, 150) pieces of A and 120 (138, 150) pieces of B, 8"/20.5cm long. Holding 3 pieces of A and 3 pieces of B together, fold the strands in half. Insert crochet hook, from RS to WS to RS again, around a stitch of the center row of Mohawk strip and into the folded strands. Draw the fold back around the stitch to the RS, forming a loop on the RS. Insert ends of strands into the loop and pull to tighten. Repeat this process to attach fringe to all of the sc in the center row of Mohawk strip. Trim fringe to about 2"/5cm long.
Lightly block hat and skull. Sew skull to one side of hat. Sew Mohawk strip to center of hat, beginning at center front of hat, and sew evenly across top of hat to center back.
Ties (make 2): Cut 9 strands of A, 20"/51cm long. Divide strands into 3 groups of 2 strands each and braid strands. Tie a knot at each end to secure. Sew one end of one tie to point of each earflap.
Pompoms: Make 2"/5cm pompoms using equal amounts of A and B. Sew one pompom to end of each tie.
Using yarn needle, weave in all ends.