---- Minecraft Crash Report ----
// This is a token for 1 free hug. Redeem at your nearest Mojangsta: _HUG~

Time: 08.12.15 19:53
Description: Ticking entity

java.lang.NullPointerException: Ticking entity
at aaa.a(SourceFile:44)
at zu.m(SourceFile:117)
at ahn.a(SourceFile:1467)
at lp.a(SourceFile:719)
at ahn.g(SourceFile:1445)
at ahn.k(SourceFile:1335)
at lp.k(SourceFile:552)
at net.minecraft.server.MinecraftServer.D(SourceFile:625)
at net.minecraft.server.MinecraftServer.C(SourceFile:553)
at bxz.C(SourceFile:154)
at net.minecraft.server.MinecraftServer.run(SourceFile:457)
at java.lang.Thread.run(Thread.java:745)

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

– Head –
Stacktrace:
at aaa.a(SourceFile:44)
at zu.m(SourceFile:117)
at ahn.a(SourceFile:1467)
at lp.a(SourceFile:719)
at ahn.g(SourceFile:1445)

– Entity being ticked –
Details:
Entity Type: SmallFireball (aaa)
Entity ID: 241
Entity Name: Малый огненный шар
Entity's Exact location: 61,30, 68,51, 100,95
Entity's Block location: World: (61,68,100), Chunk: (at 13,4,4 in 3,6; contains blocks 48,0,96 to 63,255,111), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Entity's Momentum: -0,03, 0,00, -0,09
Entity's Passengers: []
Entity's Vehicle: ~_ERROR~ NullPointerException: null
Stacktrace:
at ahn.k(SourceFile:1335)
at lp.k(SourceFile:552)

– Affected level –
Details:
Level name: survival_1.9
All players: 1 total; [lr['KlarOFF'/171, l='survival_1.9', x=57,76, y=67,00, z=85,43]]
Chunk stats: ServerChunkCache: 341 Drop: 49
Level seed: 5444404004901582403
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (0,0,0), Chunk: (at 0,0,0 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: ~_ERROR~ NullPointerException: null
Stacktrace:
at net.minecraft.server.MinecraftServer.D(SourceFile:625)
at net.minecraft.server.MinecraftServer.C(SourceFile:553)
at bxz.C(SourceFile:154)
at net.minecraft.server.MinecraftServer.run(SourceFile:457)
at java.lang.Thread.run(Thread.java:745)

– System Details –
Details:
Minecraft Version: 15w49b
Operating System: Windows 8.1 (amd64) version 6.3
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 79610376 bytes (75 MB) / 392691712 bytes (374 MB) up to 954728448 bytes (910 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Profiler Position: N/A (disabled)
Player Count: 1 / 8; [lr['KlarOFF'/171, l='survival_1.9', x=57,76, y=67,00, z=85,43]]
Type: Integrated Server (map_client.txt)
Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.