Question: What episode of legends of tomorrow is the crossover?
Answer: Invasion !
Disambiguated annotations:
qaPairs: question: What episode of legends of tomorrow is the "Invasion!" crossover?
answer: 23
question: What episode of legends of tomorrow is the "Crisis on Earth-X, Part 4" crossover?
answer: 41
question: What episode of legends of tomorrow is the "Crisis on Infinite Earths: Part Five" crossover?
answer: 68