what happens if you dont have a character when you rebirth in diablo 3?

Given that Blizzard is pushing for a live service structure with Diablo 4, there's a good chance that the cap will one day rise via one of the Seasons in the new Diablo 4 Battle Pass. Paragon levels are, in essence, an alternative progression model that rewards you for playing at max level and allows you to get stronger on all of your characters while earning those Paragon levels.

While the Diablo 4 level cap is currently 100, this may change in the future Diablo 3 launched with a level cap of 60 and ultimately saw its max level rise to 70 with the Reaper of Souls expansion. You'll also need to complete more challenging Nightmare Dungeons unlocked by the higher Diablo 4 World Tiers. Reaching the Diablo 4 level cap of 100 is therefore the endgame grind and using Paragon Points allows you to further enhance your build with creative and destructive upgrade nodes. Now you need to earn far more XP to level up but you'll get four Paragon Points along each level for a total of 200 (you can get an extra 20 points from Renown tier rewards too).

For Level 50-100, you no longer earn Skill Points and instead move to the Diablo 4 Paragon Board. However, once you hit level 50, the leveling rewards change entirely.

What happens if you dont have a character when you rebirth in diablo 3?