Do creatures come into play tapped if they come into play at the same time as a card which says “Creatures come into play tapped”?

Question

An example situation :

Living Death resolves while there is a Urabrask the Hidden in my graveyard and another creature in my opponent's graveyard. Urabrask says "Creatures your opponents control enter the battlefield tapped."

Will my opponent's creature come into play tapped if it enters the battlefield at the same time as Urabrask?

Answer 1

No, your opponent's creatures will not enter tapped.

The ability "Creatures your opponents control enter the battlefield tapped" creates a replacement effect on creatures entering the battlefield. Rule 614.4 says

Replacement effects must exist before the appropriate event occurs -- they can't "go back in time" and change something that's already happened.

Since your Urabrask wasn't on the battlefield before your opponent's creature entered, it's ability does not effect that creatures.