Hopper: java.lang.ClassCastException: dm cannot be cast to dk

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-197304/

Crash:

java.lang.ClassCastException: dm cannot be cast to dk
	at de.l(SourceFile:194)

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

---- Minecraft Crash Report ----
// Don't be sad. I'll do better next time, I promise!

Time: 2013-09-20 17:54
Description: Reading NBT data

java.lang.ClassCastException: dm cannot be cast to dk
	at de.l(SourceFile:194)
	at bgw.h(SourceFile:87)
	at bhf.a(SourceFile:64)
	at awp.o(SourceFile:1507)
	at awp.aa(SourceFile:726)
	at awp.e(SourceFile:677)
	at net.minecraft.client.main.Main.main(SourceFile:104)


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

-- Head --
Stacktrace:
	at de.l(SourceFile:194)

-- Corrupt NBT tag --
Details:
	Tag type found: LIST
	Tag type expected: INT[]
	Tag name: Colors
Stacktrace:
	at de.l(SourceFile:194)
	at bgw.h(SourceFile:87)

-- Particle being ticked --
Details:
	Particle: bgw, Pos (-1555.5,66.19250000000001,785.5), RGBA (1.0,1.0,1.0,1.0), Age 0
	Particle Type: MISC_TEXTURE
Stacktrace:
	at bhf.a(SourceFile:64)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bgh['goodsax'/58439, l='MpServer', x=-1557,46, y=57,62, z=782,06]]
	Chunk stats: MultiplayerChunkCache: 225, 225
	Level seed: 0
	Level generator: ID 01 - flat, ver 0. Features enabled: false
	Level generator options: 
	Level spawn location: World: (-1549,4,777), Chunk: (at 3,0,9 in -97,48; contains blocks -1552,0,768 to -1537,255,783), Region: (-4,1; contains chunks -128,32 to -97,63, blocks -2048,0,512 to -1537,255,1023)
	Level time: 2770 game time, 2770 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: 2 total; [bgh['goodsax'/58439, l='MpServer', x=-1557,46, y=57,62, z=782,06], vl['entity.FireworksRocketEntity.name'/186901, l='MpServer', x=-1555,50, y=66,19, z=785,50]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bgc.a(SourceFile:297)
	at awp.b(SourceFile:1874)
	at awp.e(SourceFile:686)
	at net.minecraft.client.main.Main.main(SourceFile:104)

-- System Details --
Details:
	Minecraft Version: 13w38c
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 46172424 bytes (44 MB) / 308019200 bytes (293 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 247 (13832 bytes; 0 MB) allocated, 138 (7728 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Launched Version: 13w38c
	LWJGL: 2.9.0
	OpenGL: GeForce GT 555M/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: 69 (3864 bytes; 0 MB) allocated, 16 (896 bytes; 0 MB) used

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-197304/12626653/