I tried to summon a dragon so i could find out how to get the dragon breath then my minecraft crashed heres the crash code:

---- Minecraft Crash Report ----
// On the bright side, I bought you a teddy bear!

Time: 8/12/15 5:53 PM
Description: Rendering entity in world

java.lang.NullPointerException: Rendering entity in world
at qq.aD(SourceFile:1642)
at qq.e(SourceFile:1633)
at bny.a(SourceFile:446)
at bob.b(SourceFile:23)
at bob.a(SourceFile:16)
at bny.b(SourceFile:428)
at bny.a(SourceFile:28)
at bni.a(SourceFile:46)
at bny.a(SourceFile:185)
at bob.a(SourceFile:41)
at bob.a(SourceFile:16)
at bnh.a(SourceFile:302)
at bnh.a(SourceFile:267)
at bnh.a(SourceFile:234)
at bjn.a(SourceFile:605)
at bjg.a(SourceFile:1253)
at bjg.b(SourceFile:1158)
at bjg.a(SourceFile:1005)
at ayt.au(SourceFile:903)
at ayt.a(SourceFile:326)
at net.minecraft.client.main.Main.main(SourceFile:125)

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

– Head –
Stacktrace:
at qq.aD(SourceFile:1642)
at qq.e(SourceFile:1633)
at bny.a(SourceFile:446)
at bob.b(SourceFile:23)
at bob.a(SourceFile:16)
at bny.b(SourceFile:428)
at bny.a(SourceFile:28)
at bni.a(SourceFile:46)
at bny.a(SourceFile:185)
at bob.a(SourceFile:41)
at bob.a(SourceFile:16)

– Entity being rendered –
Details:
Entity Type: Pig (vc)
Entity ID: 9835
Entity Name: Pig
Entity's Exact location: -36.94, 70.66, 314.53
Entity's Block location: -37.00,70.00,314.00 - World: (-37,70,314), Chunk: (at 11,4,10 in -3,19; contains blocks -48,0,304 to -33,255,319), 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
Entity's Rider: ~_ERROR~ NullPointerException: null
Entity's Vehicle: ~_ERROR~ NullPointerException: null

– Renderer details –
Details:
Assigned renderer: bof@440309c5
Location: -0.02,-0.02,-0.02 - World: (-1,-1,-1), Chunk: (at 15,-1,15 in -1,-1; contains blocks -16,0,-16 to -1,255,-1), Region: (-1,-1; contains chunks -32,-32 to -1,-1, blocks -512,0,-512 to -1,255,-1)
Rotation: 0.0
Delta: 0.45883518
Stacktrace:
at bnh.a(SourceFile:302)
at bnh.a(SourceFile:267)
at bnh.a(SourceFile:234)
at bjn.a(SourceFile:605)
at bjg.a(SourceFile:1253)
at bjg.b(SourceFile:1158)

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [bit['Guyalf1TheGamer'/176, l='MpServer', x=-36.92, y=70.68, z=314.55]]
Chunk stats: MultiplayerChunkCache: 1053, 1053
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: -52.00,64.00,256.00 - World: (-52,64,256), Chunk: (at 12,4,0 in -4,16; contains blocks -64,0,256 to -49,255,271), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 3942 game time, 3942 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: 89 total; [xn['Creeper'/7192, l='MpServer', x=-62.50, y=15.00, z=303.50], ye['Zombie'/7195, l='MpServer', x=-50.66, y=16.00, z=293.28], ya['Skeleton'/8225, l='MpServer', x=-38.50, y=21.00, z=293.50], vc['Pig'/61, l='MpServer', x=-71.09, y=64.00, z=258.69], vc['Pig'/62, l='MpServer', x=-96.16, y=66.00, z=249.13], vc['Pig'/63, l='MpServer', x=-91.47, y=65.00, z=256.06], vc['Pig'/64, l='MpServer', x=-86.72, y=69.00, z=256.47], vc['Pig'/66, l='MpServer', x=-58.09, y=64.00, z=259.22], wz['item.tile.mushroom'/68, l='MpServer', x=-86.88, y=11.00, z=259.78], vc['Pig'/69, l='MpServer', x=-75.66, y=64.00, z=360.53], vc['Pig'/70, l='MpServer', x=-77.09, y=64.00, z=358.78], vc['Pig'/71, l='MpServer', x=-70.09, y=64.00, z=353.88], vc['Pig'/72, l='MpServer', x=-79.94, y=64.00, z=360.00], xn['Creeper'/8269, l='MpServer', x=-103.63, y=32.00, z=255.97], ux['Cow'/83, l='MpServer', x=-62.00, y=64.00, z=362.25], ux['Cow'/84, l='MpServer', x=-61.22, y=64.00, z=360.16], ux['Cow'/85, l='MpServer', x=-58.50, y=65.00, z=366.50], ux['Cow'/86, l='MpServer', x=-58.50, y=65.00, z=366.50], ve['Sheep'/100, l='MpServer', x=19.56, y=64.00, z=373.47], ve['Sheep'/101, l='MpServer', x=22.47, y=64.00, z=372.88], ve['Sheep'/102, l='MpServer', x=22.94, y=64.00, z=374.97], ve['Sheep'/103, l='MpServer', x=21.00, y=64.00, z=373.66], bit['Guyalf1TheGamer'/176, l='MpServer', x=-47.60, y=64.00, z=262.70], yc['Spider'/9416, l='MpServer', x=-80.50, y=41.00, z=235.50], ya['Skeleton'/9433, l='MpServer', x=-36.50, y=13.00, z=339.50], ya['Skeleton'/8416, l='MpServer', x=-54.72, y=13.00, z=349.41], xn['Creeper'/9509, l='MpServer', x=-56.97, y=48.00, z=287.44], ya['Skeleton'/8500, l='MpServer', x=-45.13, y=14.00, z=340.41], ye['Zombie'/9540, l='MpServer', x=-75.72, y=16.00, z=291.50], ya['Skeleton'/8517, l='MpServer', x=-93.50, y=41.00, z=243.50], yc['Spider'/9542, l='MpServer', x=-76.00, y=17.00, z=292.97], yc['Spider'/9544, l='MpServer', x=-48.31, y=18.09, z=291.69], ut['Bat'/9564, l='MpServer', x=-96.41, y=29.00, z=258.69], ut['Bat'/9566, l='MpServer', x=-101.47, y=17.97, z=259.16], ut['Bat'/9579, l='MpServer', x=-64.59, y=22.00, z=298.44], ut['Bat'/9580, l='MpServer', x=-43.75, y=13.81, z=296.75], ut['Bat'/9581, l='MpServer', x=-50.91, y=19.09, z=297.31], ya['Skeleton'/8601, l='MpServer', x=22.50, y=19.00, z=305.50], ya['Skeleton'/8602, l='MpServer', x=22.50, y=19.00, z=306.50], ya['Skeleton'/6613, l='MpServer', x=4.50, y=12.00, z=315.50], yc['Spider'/9693, l='MpServer', x=-98.50, y=35.00, z=270.50], ye['Zombie'/8681, l='MpServer', x=-30.09, y=23.00, z=265.63], ye['Zombie'/8682, l='MpServer', x=-32.50, y=21.00, z=263.50], ye['Zombie'/9721, l='MpServer', x=-113.50, y=51.00, z=373.50], ye['Zombie'/9722, l='MpServer', x=-114.50, y=51.00, z=373.50], ye['Zombie'/9723, l='MpServer', x=-113.50, y=51.00, z=372.50], wz['item.item.rottenFlesh'/5646, l='MpServer', x=-34.97, y=19.00, z=277.78], ye['Zombie'/8751, l='MpServer', x=-104.50, y=41.00, z=259.50], yc['Spider'/9776, l='MpServer', x=-39.50, y=19.00, z=252.50], ya['Skeleton'/9777, l='MpServer', x=-104.50, y=42.00, z=267.50], xn['Creeper'/9792, l='MpServer', x=16.50, y=18.00, z=301.50], xn['Creeper'/7767, l='MpServer', x=-79.69, y=20.00, z=305.50], ya['Skeleton'/7768, l='MpServer', x=-72.50, y=20.00, z=299.50], ya['Skeleton'/7773, l='MpServer', x=-64.53, y=13.00, z=238.69], ye['Zombie'/8809, l='MpServer', x=-38.50, y=24.00, z=268.50], ye['Zombie'/8810, l='MpServer', x=-34.50, y=24.00, z=270.50], ye['Zombie'/8811, l='MpServer', x=-20.50, y=21.00, z=285.50], vc['Pig'/9835, l='MpServer', x=-36.94, y=70.66, z=314.53], bit['Guyalf1TheGamer'/176, l='MpServer', x=-36.92, y=70.68, z=314.55], ya['Skeleton'/6792, l='MpServer', x=31.69, y=24.00, z=274.50], xn['Creeper'/7886, l='MpServer', x=-33.50, y=46.00, z=326.50], xn['Creeper'/7888, l='MpServer', x=-72.28, y=17.00, z=264.72], ye['Zombie'/8914, l='MpServer', x=-28.50, y=21.00, z=268.50], ye['Zombie'/8915, l='MpServer', x=-30.50, y=21.00, z=264.50], yc['Spider'/8952, l='MpServer', x=-26.50, y=18.00, z=295.50], xn['Creeper'/8954, l='MpServer', x=-28.50, y=18.00, z=296.50], xn['Creeper'/8955, l='MpServer', x=-31.63, y=18.00, z=291.56], ut['Bat'/8979, l='MpServer', x=3.24, y=13.92, z=327.17], ut['Bat'/8980, l='MpServer', x=4.48, y=13.05, z=324.59], ut['Bat'/8982, l='MpServer', x=5.49, y=15.06, z=318.90], ut['Bat'/8983, l='MpServer', x=-46.40, y=15.00, z=318.11], ut['Bat'/8984, l='MpServer', x=-35.49, y=12.85, z=336.68], ut['Bat'/8994, l='MpServer', x=-23.63, y=22.92, z=267.77], ya['Skeleton'/9007, l='MpServer', x=-74.91, y=22.00, z=310.47], ya['Skeleton'/9017, l='MpServer', x=-80.50, y=34.00, z=318.50], ya['Skeleton'/9053, l='MpServer', x=41.81, y=34.00, z=347.38], ut['Bat'/8045, l='MpServer', x=26.22, y=18.10, z=291.25], ya['Skeleton'/9081, l='MpServer', x=-75.50, y=21.00, z=304.50], ya['Skeleton'/9082, l='MpServer', x=-72.50, y=21.00, z=300.88], ut['Bat'/8061, l='MpServer', x=24.66, y=16.38, z=284.97], xn['Creeper'/9142, l='MpServer', x=27.50, y=16.00, z=290.50], ye['Zombie'/9143, l='MpServer', x=27.50, y=16.00, z=288.50], ya['Skeleton'/8131, l='MpServer', x=-112.50, y=36.00, z=297.50], ya['Skeleton'/9166, l='MpServer', x=30.88, y=24.00, z=274.47], ut['Bat'/9183, l='MpServer', x=3.31, y=15.94, z=326.22], ut['Bat'/9184, l='MpServer', x=21.50, y=17.10, z=303.75], ut['Bat'/9185, l='MpServer', x=16.63, y=14.59, z=307.72], ye['Zombie'/9206, l='MpServer', x=6.91, y=18.00, z=234.38], ye['Zombie'/9207, l='MpServer', x=6.66, y=18.00, z=237.16]]
Retry entities: 0 total; []
Server brand: vanilla
Server type: Integrated singleplayer server
Stacktrace:
at bgv.a(SourceFile:314)
at ayt.b(SourceFile:2301)
at ayt.a(SourceFile:335)
at net.minecraft.client.main.Main.main(SourceFile:125)

– System Details –
Details:
Minecraft Version: 15w33a
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 208592912 bytes (198 MB) / 666644480 bytes (635 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Launched Version: 15w33a
LWJGL: 2.9.4
OpenGL: GeForce GTX 560 Ti/PCIe/SSE2 GL version 4.5.0 NVIDIA 353.62, NVIDIA Corporation
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs:
Current Language: English (UK)
Profiler Position: N/A (disabled)
CPU: 8x Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz