Hopper: java.lang.NullPointerException: Invalid Biome id

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-448526/

Crash:

java.lang.NullPointerException: Invalid Biome id
	at agm.a(SourceFile:82)

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

---- Minecraft Crash Report ----
// Why did you do that?

Time: 23-10-13 14:20
Description: Invalid Biome id

java.lang.NullPointerException: Invalid Biome id
	at agm.a(SourceFile:82)
	at agk.<init>(SourceFile:26)
	at agj.a(SourceFile:52)
	at agj.b(SourceFile:61)
	at agm.a(SourceFile:61)
	at aoi.a(SourceFile:933)
	at afm.a(SourceFile:116)
	at afm.a(SourceFile:1047)
	at blj.i(SourceFile:1327)
	at blj.a(SourceFile:919)
	at blj.b(SourceFile:813)
	at azc.ad(SourceFile:780)
	at azc.e(SourceFile:704)
	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 agm.a(SourceFile:82)

-- DownfallBlock --
Details:
	biome id: 0
	downfalls[] size: 256
	x: 0
	z: 0
	w: 16
	h: 16
Stacktrace:
	at agm.a(SourceFile:82)
	at agk.<init>(SourceFile:26)
	at agj.a(SourceFile:52)
	at agj.b(SourceFile:61)
	at agm.a(SourceFile:61)
	at aoi.a(SourceFile:933)

-- 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 afm.a(SourceFile:116)
	at afm.a(SourceFile:1047)
	at blj.i(SourceFile:1327)
	at blj.a(SourceFile:919)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bjd['geertking9'/132, 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: (53,63,270), Chunk: (at 5,3,14 in 3,16; contains blocks 48,0,256 to 63,255,271), 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: creative (ID 1). Hardcore: false. Cheats: false
	Forced entities: 1 total; [bjd['geertking9'/132, 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 biy.a(SourceFile:284)
	at azc.b(SourceFile:1949)
	at azc.e(SourceFile:713)
	at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
	Minecraft Version: 1.7.1
	Operating System: Windows 7 (x86) version 6.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 106884360 bytes (101 MB) / 190218240 bytes (181 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: 0, tcache: 0, allocated: 17, tallocated: 154
	Launched Version: 1.7.1
	LWJGL: 2.9.0
	OpenGL: GeForce GT 610/PCIe/SSE2 GL version 4.3.0, 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: 18 (1008 bytes; 0 MB) allocated, 18 (1008 bytes; 0 MB) used
	Anisotropic Filtering: Off (1)

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-448526/20787549/