The game crashed when I tried to harvest some sugarcane. It seemed generally unstable prior to that. It took three world generations for me to be able to even play. The first one put me inside a mountain, the second one did the same thing and I could not interact with the environment.
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I could not find any existing issue that contains any of the crashes mentioned here. However, all of the crash reports that you have provided are from a modded version of Minecraft. Please try to reproduce the crash in a vanilla (non-modded) version of Minecraft and attach that report or this may be dismissed as being caused by a mod.
Unable to reproduce, please redownload the snapshot as this might be fixed in the "ninja-version".
And please make sure not to mod the jar!
Dinnerbone fixed this :)Just re-download the snapshot
Bug still occurs on servers only
Redownload server jar/exe!
Redownloaded server jar and issue still occurs. I have a new crash report here
I had issues with crashing after redownloading yesterday. I re-redownloaded today, and the issues appear to be gone now.