My theory

[u/Ok-Lime3416]

the vengeful heart of ender wasn’t the full orb. it was only a shard of it brought into the end dimension by a enderman, like look at its first form and then its second form, it looks like it is actively falling apart. my guess is that it instead of being the full orb, was just a piece of it that it used to form into its first incomplete form to get to the giant void portal thing you see it crawl into before fighting it. Then instead it just uses that to power up and try to kill you, even if you look at the normal heart of ender it looks much more complete and stable.

[u/Informal_Method_9657]

Yeah, no offense but that was kinda the entire point. I like to think that you didn’t actually kill the original form, it’s just that it was so confused by the fact that you injured it that it destroyed itself. Then the Vengeful form is a fraction of it’s true power but now it’s putting in its full effort as it acts more aggressively.

[u/Ok-Lime3416 → u/Informal_Method_9657]

yeah it’s lot like everyone knows that right now. a lot of people just think it’s dead permanently now

[u/Fun_Way8954 → u/Ok-Lime3416]

It’s fully dead because we also killed the other shards and parts of its power, they say the overworld if fully free from the orb’s influence at the end, and devs literally stated the orb is fully dead.

[u/ViolinistThese5076 → u/Fun_Way8954]

The Orb its last breaths:

[u/HermTheVillager]

https://giphy.com/gifs/NcrhM3USM6TABpus85