at ri.h(SourceFile:171)
        at afn.a(SourceFile:1368)
        at mj.a(SourceFile:480)
        at afn.g(SourceFile:1346)
        at afn.h(SourceFile:1253)
        at mj.h(SourceFile:365)
        at net.minecraft.server.MinecraftServer.u(SourceFile:511)
        at lj.u(SourceFile:265)
        at net.minecraft.server.MinecraftServer.t(SourceFile:441)
        at net.minecraft.server.MinecraftServer.run(SourceFile:358)
        at ky.run(SourceFile:617)


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

-- Head --
Stacktrace:
        at ayl.a(SourceFile:26)
        at ayk.c(SourceFile:59)
        at aki.f(SourceFile:169)
        at aki.a(SourceFile:192)
        at afn.a(SourceFile:1513)
        at qn.N(SourceFile:752)
        at qn.C(SourceFile:355)
        at rh.C(SourceFile:168)
        at ri.C(SourceFile:130)
        at vg.C(SourceFile:52)
        at qn.h(SourceFile:294)
        at rh.h(SourceFile:1178)
        at ri.h(SourceFile:171)
        at afn.a(SourceFile:1368)
        at mj.a(SourceFile:480)
        at afn.g(SourceFile:1346)

-- Entity being ticked --
Details:
        Entity Type: Squid (ve)
        Entity ID: 49
        Entity Name: Squid
        Entity's Exact location: -180.22, 58.00, 334.20
        Entity's Block location: World: (-181,58,334), Chunk: (at 11,3,14 in -12,20; contains blocks -192,0,320 to -177,255,335), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
        Entity's Momentum: 0.00, 0.00, 0.00
Stacktrace:
        at afn.h(SourceFile:1253)
        at mj.h(SourceFile:365)

-- Affected level --
Details:
        Level name: world
        All players: 1 total; [mm['merlinar'/281, l='world', x=-148.60, y=17.00, z=334.30]]
        Chunk stats: ServerChunkCache: 1169 Drop: 0
        Level seed: 5215566843995100882
        Level generator: ID 00 - default, ver 1. Features enabled: true
        Level generator options:
        Level spawn location: World: (-16,64,228), Chunk: (at 0,4,4 in -1,14; contains blocks -16,0,224 to -1,255,239), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
        Level time: 47612926 game time, 47756144 day time
        Level dimension: 0
        Level storage version: 0x04ABD - Anvil
        Level weather: Rain time: 73085 (now: false), thunder time: 41228 (now: false)
        Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
        at net.minecraft.server.MinecraftServer.u(SourceFile:511)
        at lj.u(SourceFile:265)
        at net.minecraft.server.MinecraftServer.t(SourceFile:441)
        at net.minecraft.server.MinecraftServer.run(SourceFile:358)
        at ky.run(SourceFile:617)

-- System Details --
Details:
        Minecraft Version: 1.7.2
        Operating System: Linux (amd64) version 3.8.0-33-generic
        Java Version: 1.7.0_45, Oracle Corporation
        Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
        Memory: 155641696 bytes (148 MB) / 288882688 bytes (275 MB) up to 954728448 bytes (910 MB)
        JVM Flags: 1 total; -Xmx1024M
        AABB Pool Size: 6094 (341264 bytes; 0 MB) allocated, 411 (23016 bytes; 0 MB) used
        IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
        Profiler Position: N/A (disabled)
        Vec3 Pool Size: 1500 (84000 bytes; 0 MB) allocated, 153 (8568 bytes; 0 MB) used
        Player Count: 1 / 10; [mm['merlinar'/281, l='world', x=-148.60, y=17.00, z=334.30]]
        Is Modded: Unknown (can't tell)
        Type: Dedicated Server (map_server.txt)