chanciest
ˈtʃɑːnsi
adjective
involving risks and uncertainty.
football coaching is a chancy business
risky,unpredictable,uncertain,speculative,precarious,problematical,unsettled,unsafe,insecure,exposed,touch-and-go,tricky,treacherous,dangerous,fraught with danger,high-risk,hazardous,perilous,dicey,sticky,hairy,dodgy,gnarly,parlous