every time I try to play in a Minecraft server, it crashes the game.

*What I expected to happen was to be able to play some Minecraft mini-games, like egg wars (cubecraft), x run (rsmv.net), or gravity (The Hive).
*What actually happened was every time I spawned in the lobby, my Minecraft crashed.
Steps to Reproduce:
1. go into Minecraft
2. join a server
3. Minecraft crashes