Recently in my world I dug a big whole down through bedrock as I was creating a map to see what it would look like on it Minecraft crashed saying---- Minecraft Crash Report ----
// Daisy, daisy...

Time: 10/19/13 6:19 PM
Description: Ticking player

java.lang.NullPointerException: Ticking player
at abq.a(SourceFile:150)
at abq.a(SourceFile:203)
at abm.a(SourceFile:331)
at xg.k(SourceFile:203)
at xi.e(SourceFile:430)
at re.h(SourceFile:1200)
at xi.h(SourceFile:240)
at ml.i(SourceFile:207)
at mv.a(SourceFile:202)
at iq.a(SourceFile:137)
at is.a(SourceFile:20)
at el.a(SourceFile:145)
at mr.c(SourceFile:134)
at net.minecraft.server.MinecraftServer.u(SourceFile:529)
at net.minecraft.server.MinecraftServer.t(SourceFile:441)
at bsb.t(SourceFile:117)
at net.minecraft.server.MinecraftServer.run(SourceFile:358)
at kx.run(SourceFile:617)

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

– Head –
Stacktrace:
at abq.a(SourceFile:150)
at abq.a(SourceFile:203)
at abm.a(SourceFile:331)
at xg.k(SourceFile:203)
at xi.e(SourceFile:430)
at re.h(SourceFile:1200)
at xi.h(SourceFile:240)

– Player being ticked –
Details:
Entity Type: null (ml)
Entity ID: 747
Entity Name: zXTheDEATHSXz
Entity's Exact location: 511.40, 67.25, 354.03
Entity's Block location: World: (511,67,354), Chunk: (at 15,4,2 in 31,22; contains blocks 496,0,352 to 511,255,367), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Entity's Momentum: 0.00, 0.00, 0.00
Stacktrace:
at ml.i(SourceFile:207)
at mv.a(SourceFile:202)
at iq.a(SourceFile:137)
at is.a(SourceFile:20)
at el.a(SourceFile:145)

– Ticking connection –
Details:
Connection: el@ce7967
Stacktrace:
at mr.c(SourceFile:134)
at net.minecraft.server.MinecraftServer.u(SourceFile:529)
at net.minecraft.server.MinecraftServer.t(SourceFile:441)
at bsb.t(SourceFile:117)
at net.minecraft.server.MinecraftServer.run(SourceFile:358)
at kx.run(SourceFile:617)

– System Details –
Details:
Minecraft Version: 13w42a
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: 172649912 bytes (164 MB) / 375656448 bytes (358 MB) up to 518979584 bytes (494 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
AABB Pool Size: 2721 (152376 bytes; 0 MB) allocated, 2663 (149128 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Profiler Position: N/A (disabled)
Vec3 Pool Size: 1330 (74480 bytes; 0 MB) allocated, 1301 (72856 bytes; 0 MB) used
Player Count: 1 / 8; [ml['zXTheDEATHSXz'/747, l='Green Haven PVP', x=511.40, y=67.25, z=354.03]]
Type: Integrated Server (map_client.txt)
Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.
Hopefully someone could help me. Anything would be greatly appreciated.