What is the antonym of Exodus?

Exodus means leaving, so some antonyms for it would be remaining and staying.

Would "Migration to" be a better alternative Exodus means Going away in numbers... so... the opposite could be "coming in, in big numbers" ?

The opposite of and exodus would possibly be Advent if you're looking for nice Words. :)

Thanks so much for this answer, I could not find it anywhere and it's due for my homework in my English class tomorrow!!