Describe the bug
Game crash:
It appears when someone enters the server or dies.
Additionally, if someone dies, this crash kicks that person out of the server.
All players struggle with this issue.

To Reproduce
Steps to reproduce the behavior:

• Enter the server
• Try to respawn
  => Crash

Expected behavior
Normal joining/respawning; no crash

Minecraft and Hunter's Dream version
Minecraft 1.12.2, Hunter's Dream 1.1.2 (newest as of now)

Crash report or log
https://pastebin.com/raw/v8hSZjDR

Additional context
Multiplayer and packet-related issue

Quoting myself from Discord:

Hm, interesting that you're the first to report that, iirc that issue hasn't come up yet.
So the cause seems to be the transformation packet. It's sent when you join a server, die, transform or change your transformation, which makes sense considering that's also when you reported it to crash.
The crash is client side only and is caused by the id of the player not being found. In hindsight, it was probably a bad idea of mine to just throw an exception here (I hope the new version will be less prone to errors like that).

The bug has been fixed and a new version (Hunter's Dream 1.1.3) is available now.
This has also been thoroughly tested on a server, so it should no longer crash now.