The phrase "came to scratch" is often used to describe someone who is ready and prepared for a challenge, especially a physical one. However, there are many different phrases and words that can be used as synonyms for this expression, including "stepped up to the plate", "rose to the occasion", "was game for", "took on the challenge", and "showed up ready to play". Regardless of the exact wording, these expressions all imply a sense of readiness, determination, and willingness to face any obstacle head-on and come out victorious. If you want to describe someone who is always up for a challenge, there are plenty of ways to do so without using the phrase "came to scratch".