"Be spoiling for" is an idiomatic expression that means to be eager and ready for a fight or confrontation. There are several synonyms that can be used in place of this phrase such as itching for, craving, thirsting for, hankering after, or yearning for. All of these alternatives convey the same level of eagerness and readiness for action but with slightly different nuances. For example, "itching for" implies a restlessness and impatience, while "craving" suggests a strong desire, and "yearning for" conveys a deep emotional longing. Using synonyms can help add variety to your writing and convey your message with greater precision.