[Issue Report]: TCP multiplayer out-of-sync after dying, monsters killed by a player don't die for the other one

[nor-ric]

Operating System

Linux x64

DevilutionX version

1.5.2

Describe

I've just experienced a strange out-of-sync issue, in a TCP multiplayer game. I was the host, the other player was the guest.
All started when the other player died (first time dying in this game session) and restarted in town. Then he came down to crypt level 4 with a town portal I opened for him. I think in the meanwhile I also went to town with such portal, even though I'm not 100% sure.
By the way, when we both went down again through the portal, the following happened:

• every monster I killed, didn't die in his game
  

• his game was full of monsters which I couldn't even see in mine, because I had already killed them.  He had to kill them all again by himself. While he was actually slashing those monsters with his maul, his character wasn't moving on my screen, I was seeing him as completely still.
  

• about those monsters which I did see in my game, nothing was wrong when he killed them: they died for me too
  

• we both found a perfectly identical ring of titans (I didn't notice when exactly, could be a coincidence, I don't know for sure)
  

To Reproduce

This is the first time it happened. I couldn't notice anything unusual that could have triggered this behaviour.

Expected Behavior

Of course, the game session should be in sync between the two players.

Additional context

What we tried to solve this, unsuccessfully:

• go up and down again with another town portal
  

• he died once more and restarted in town
  

• not sure about this, but I think I tried to die myself and restart in town
  

• he exited from the game and joined again (I couldn't try this myself because I was the host)