They are sewn to the head and neck.
R 1: 5 sc in mc (5)
R 2: 5 sc
R 3: (inc) x 5 (10)
Sl st. F.o. and leave a yarn tail about 10 cm long for sewing.
Spikes #2 (make 4)
They are sewn to the body and tail.
R 1: 5 sc in mc (5)
R 2: 5 sc
R 3: (inc) x 5 (10)
R 4: 10 sc
Sl st. F.o. and leave a yarn tail about 10 cm long for sewing.
How to sew the details together you may view in the video below at 26:47.