Answer: crossbones

AnswerCrossword Clue
CROSSBONES

Skull's partner

CROSSBONES

Part of a certain flag

CROSSBONES

Skull and ...

CROSSBONES
Skull's companion
CROSSBONES
Skull and ... (dire warning)
CROSSBONESPart of a symbol of danger
CROSSBONESJolly Roger's dark side?
CROSSBONESSkull accompanier