True, "it is appointed for men to die once, but after this the judgment" (Heb. 9:27). But saved people are judged in order to receive rewards for anything good they did, their salvation was assured beforehand. I like to compare it to Awards Day at school, some students get several awards, others only one or two, but even those without any awards can still be promoted to the next grade. The unsaved have to wait for the resurrection after the Millennial Kingdom (Rev. 20:11-15) where their actions are judged also, but we know that if they had to wait until this time it means that their names are not in the Lamb's Book of Life and they are going to be thrown in the Lake of Fire for eternity.
Then no one dies. And Satan was correct.