I will not initiate a crossover with any incarnation of the Justice League/X-Men.
Emperor Maximus was wreaking havoc in Angel Grove Park. The Justice League and the X-Men battled Emperor Maximus, but they needed help. So Zordon and Alpha 5 summoned the Power Rangers to the Command Center. The Rangers saw what was going on in Angel Grove Park and they morphed into action. The Rangers said "We need Thunder MegaFalconzord power, now!" Thunder MegaFalconzord swooped into action and battled Emperor Maximus. With a swing of the mighty Zord's sword, Emperor Maximus was destroyed. Angel Grove was safe once more. Thanks, Rangers!