Adjective
resounding - Referring to something that is striking, definite, or leaves a strong impression, such as a victory or success.

The season concluded with a resounding victory, with the team winning by a margin so large it left no doubt about their superiority.
unforgiving - Not making an allowance for error or weakness in others; not willing to forgive others for things they might have done wrong.

Because they knew that Alaska in the winter is an unforgiving environment, they had to plan their expedition very carefully.