76. This was the LAST episode where aliens attempt to seize control of Voyager upon entering the bridge.
From Quiz Name That Episode #39
Answer:
Q2
Another one to think about, but in general, there were less enemy alien takeover attempts in the latter part of the series than in earlier seasons. In the the third and final Q episode, "Q2", Q Junior summoned the Borg cubes and caused several drones to board the bridge as part of his annoying antics to get Janeway's attention. Although it was unknown if the Borg really were wanting to take control of Voyager, it has to be assumed that, given the Borg's nature of always wanting to assimilate other species and being presented with the opportunity to seize another Federation ship into their massive collective, that they wanted to do exactly that. "Prophecy" did show the mighty Klingons attempting to fulfill their decades-long mission, boarding the bridge and engaging in not a blood-shedding bat'leth melee, but a Federation-style phaser fight with the crew. However, "Prophecy" aired a few weeks BEFORE "Q2" and, thus, cannot qualify as the correct answer. "Homestead", also airing in the seventh season, did air much later than "Q2", but neither the aliens of the mining colony nor the Talaxians themselves attempted any sort of takeover of Voyager. In "Repentance", the prisoners did escape from their cells in the brig at some point, but none ever enter the bridge nor try to take control of Voyager directly. Once again, however, this episode aired BEFORE "Q2" and cannot qualify as the correct answer either.