Answer: unrivaled

AnswerCrossword Clue
UNRIVALEDWithout equal
UNRIVALEDLacking serious challenge
UNRIVALEDBy oneself
UNRIVALEDTops
UNRIVALEDPeerless.
unrivaledwithout a rival also UNRIVALLED
unrivaledBetter than everyone or everything of the same type