Hopper: java.lang.NullPointerException: Getting biome

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-397924/

Crash:

java.lang.NullPointerException: Getting biome
	at aoc.a(SourceFile:934)

The following is the first clean report made public about this crash:

---- Minecraft Crash Report ----
// Uh... Did I do that?

Time: 18/10/13 20:22
Description: Getting biome

java.lang.NullPointerException: Getting biome
	at aoc.a(SourceFile:934)
	at afk.a(SourceFile:116)
	at afk.a(SourceFile:1047)
	at blc.i(SourceFile:1321)
	at blc.a(SourceFile:918)
	at blc.b(SourceFile:813)
	at ayw.ad(SourceFile:782)
	at ayw.e(SourceFile:706)
	at net.minecraft.client.main.Main.main(SourceFile:103)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at aoc.a(SourceFile:934)

-- Coordinates of biome request --
Details:
	Location: World: (8,0,8), Chunk: (at 8,0,8 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Stacktrace:
	at afk.a(SourceFile:116)
	at afk.a(SourceFile:1047)
	at blc.i(SourceFile:1321)
	at blc.a(SourceFile:918)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [biw['OICelticIO'/0, l='MpServer', x=8,50, y=66,62, z=8,50]]
	Chunk stats: MultiplayerChunkCache: 0, 0
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (0,67,0), Chunk: (at 0,4,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 0 game time, 0 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
	Forced entities: 1 total; [biw['OICelticIO'/0, l='MpServer', x=8,50, y=66,62, z=8,50]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bir.a(SourceFile:284)
	at ayw.b(SourceFile:1938)
	at ayw.e(SourceFile:715)
	at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
	Minecraft Version: 13w42b
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 438940352 bytes (418 MB) / 518979584 bytes (494 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 4627 (259112 bytes; 0 MB) allocated, 4627 (259112 bytes; 0 MB) used
	IntCache: cache: 5, tcache: 127, allocated: 8, tallocated: 29
	Launched Version: 13w42b
	LWJGL: 2.9.0
	OpenGL: GeForce GT 635M/PCIe/SSE2 GL version 4.2.0, NVIDIA Corporation
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: []
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 20 (1120 bytes; 0 MB) allocated, 20 (1120 bytes; 0 MB) used
	Anisotropic Filtering: Off (1)

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-397924/19120098/