2020-06-23 : Barrin's last ability checks the entire turn, even before Barrin was on the battlefield.

2020-06-23 : If a permanent wasn't put into your hand from the battlefield before your end step begins, Barrin's ability doesn't trigger at all.

2020-06-23 : If a token is returned to your hand, it's put there before it ceases to exist.

2020-06-23 : The permanent that was returned to your hand doesn't have to still be there.

2020-06-23 : You draw only one card, no matter how many permanents were put into your hand from the battlefield during that turn.