When using the command "/give PLAYERNAME 35 1 700", which translates to wool with a data value of 700, it crashes the game. Now creating a wool block with data value of 700 is silly but I wouldn't expect it would crash just ignore my data value. If you were to do the same with glass (block 20) it will ignore you and give you data value of 0. After crashing out I just tried to reconnect and I believe the faulty entity is still around and it crashes me out immediately. Apologies if this is a dupe I have searched and did not found anything smiler.