Final answer:
Xerxes I was the Persian king who led the 2nd invasion of Greece to avenge his father's defeat. His forces were ultimately defeated by the Macedonians led by Alexander the Great.
Step-by-step explanation:
The Persian king who led the 2nd invasion of Greece to avenge his father's defeat was Xerxes I. Xerxes I was the successor of Darius I and he amassed armies to face the Greek forces led by Alexander the Great. However, his forces were ultimately defeated by the Macedonians at the battles of Issus and Gaugamela.