Ok, so I was derping around. I made the slime ice cream cone as in SethBling's video. I also added a minecart on the top of them and wanted to ride them xD. Shame it crashed when I right clicked the minecart...
---- Minecraft Crash Report ----
// Sorry

Time: 10/10/13 7:20 PM
Description: Unexpected error

java.lang.NullPointerException
at bkv.a(SourceFile:303)
at bkv.a(SourceFile:900)
at bkv.b(SourceFile:816)
at ays.ab(SourceFile:783)
at ays.e(SourceFile:706)
at net.minecraft.client.main.Main.main(SourceFile:103)

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

– Head –
Stacktrace:
at bkv.a(SourceFile:303)
at bkv.a(SourceFile:900)

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [bip['TehTotalPwnage'/322, l='MpServer', x=186.88, y=169.62, z=140.42]]
Chunk stats: MultiplayerChunkCache: 301, 301
Level seed: 0
Level generator: ID 03 - amplified, ver 0. Features enabled: false
Level generator options:
Level spawn location: World: (176,64,156), Chunk: (at 0,4,12 in 11,9; contains blocks 176,0,144 to 191,255,159), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 27684 game time, 27684 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: 80 total; [ws['Slime'/56158, l='MpServer', x=186.31, y=164.84, z=142.24], ws['Slime'/56159, l='MpServer', x=186.31, y=161.69, z=142.24], vy['entity.MinecartRideable.name'/56157, l='MpServer', x=186.31, y=168.79, z=142.24], uu['Pig'/80, l='MpServer', x=108.50, y=73.00, z=97.50], bip['TehTotalPwnage'/322, l='MpServer', x=186.88, y=169.62, z=140.42], uu['Pig'/83, l='MpServer', x=110.50, y=211.00, z=153.50], uu['Pig'/93, l='MpServer', x=112.50, y=152.00, z=98.50], uu['Pig'/95, l='MpServer', x=112.38, y=138.00, z=185.13], vq['item.item.slimeball'/55935, l='MpServer', x=190.34, y=128.13, z=186.88], uu['Pig'/103, l='MpServer', x=144.69, y=147.00, z=139.50], vq['item.item.slimeball'/56175, l='MpServer', x=233.81, y=132.13, z=152.34], ws['Slime'/55928, l='MpServer', x=153.69, y=135.00, z=178.27], ws['Slime'/55929, l='MpServer', x=178.21, y=149.00, z=161.42], ws['Slime'/56164, l='MpServer', x=186.31, y=152.69, z=142.24], ws['Slime'/56161, l='MpServer', x=186.31, y=156.74, z=142.24], uu['Pig'/106, l='MpServer', x=130.72, y=161.00, z=150.47], ws['Slime'/56160, l='MpServer', x=186.31, y=158.99, z=142.24], ws['Slime'/55923, l='MpServer', x=193.41, y=148.00, z=156.66], ws['Slime'/56163, l='MpServer', x=186.31, y=153.59, z=142.24], uu['Pig'/104, l='MpServer', x=134.97, y=142.00, z=158.09], ws['Slime'/56162, l='MpServer', x=186.31, y=154.94, z=142.24], ws['Slime'/55921, l='MpServer', x=151.60, y=139.50, z=167.35], uu['Pig'/105, l='MpServer', x=132.81, y=144.00, z=150.03], um['Chicken'/137, l='MpServer', x=180.47, y=84.00, z=214.41], um['Chicken'/136, l='MpServer', x=178.59, y=113.00, z=203.59], ws['Slime'/55956, l='MpServer', x=165.49, y=93.72, z=201.38], uu['Pig'/131, l='MpServer', x=202.91, y=145.00, z=108.81], uu['Pig'/132, l='MpServer', x=166.84, y=147.00, z=106.03], um['Chicken'/135, l='MpServer', x=180.53, y=120.00, z=200.47], um['Chicken'/134, l='MpServer', x=184.69, y=114.00, z=201.34], vq['item.item.slimeball'/55936, l='MpServer', x=196.13, y=128.13, z=181.88], vq['item.item.slimeball'/55937, l='MpServer', x=193.25, y=120.13, z=188.03], vq['item.item.slimeball'/55938, l='MpServer', x=181.69, y=122.13, z=188.66], vq['item.item.slimeball'/55940, l='MpServer', x=180.41, y=121.13, z=188.16], uu['Pig'/157, l='MpServer', x=221.10, y=150.00, z=141.07], uu['Pig'/158, l='MpServer', x=162.50, y=152.00, z=112.31], vq['item.item.slimeball'/55943, l='MpServer', x=196.88, y=111.13, z=190.41], uu['Pig'/159, l='MpServer', x=220.50, y=145.00, z=150.31], vq['item.item.slimeball'/55944, l='MpServer', x=190.78, y=99.13, z=192.13], vq['item.item.slimeball'/55949, l='MpServer', x=189.81, y=99.13, z=192.09], vq['item.item.slimeball'/55950, l='MpServer', x=186.88, y=97.13, z=192.50], ws['Slime'/55986, l='MpServer', x=189.97, y=88.00, z=197.69], ws['Slime'/55985, l='MpServer', x=198.38, y=89.00, z=195.25], ws['Slime'/55984, l='MpServer', x=205.05, y=89.04, z=197.13], vq['item.item.slimeball'/55990, l='MpServer', x=186.19, y=122.13, z=193.31], ws['Slime'/55988, l='MpServer', x=198.34, y=95.00, z=207.41], ws['Slime'/55995, l='MpServer', x=182.28, y=87.00, z=197.33], uu['Pig'/163, l='MpServer', x=204.22, y=89.00, z=202.56], uu['Pig'/162, l='MpServer', x=193.91, y=93.00, z=198.53], vq['item.item.slimeball'/55993, l='MpServer', x=196.56, y=88.13, z=196.66], uu['Pig'/161, l='MpServer', x=194.59, y=154.00, z=147.03], vq['item.item.slimeball'/55992, l='MpServer', x=190.97, y=93.13, z=194.13], uu['Pig'/160, l='MpServer', x=194.31, y=137.00, z=177.50], ws['Slime'/55999, l='MpServer', x=185.76, y=87.00, z=198.00], uu['Pig'/167, l='MpServer', x=203.50, y=78.00, z=219.31], ws['Slime'/55998, l='MpServer', x=203.72, y=92.00, z=194.34], vq['item.item.slimeball'/55997, l='MpServer', x=178.19, y=121.13, z=187.13], uu['Pig'/165, l='MpServer', x=206.31, y=76.00, z=220.56], uu['Pig'/164, l='MpServer', x=202.50, y=90.00, z=207.16], ws['Slime'/55971, l='MpServer', x=196.97, y=99.00, z=192.19], ws['Slime'/55969, l='MpServer', x=188.40, y=101.00, z=189.34], vq['item.item.slimeball'/55973, l='MpServer', x=194.50, y=93.13, z=194.25], vq['item.item.slimeball'/55978, l='MpServer', x=194.78, y=92.13, z=195.75], vq['item.item.slimeball'/55977, l='MpServer', x=192.78, y=88.13, z=196.63], ws['Slime'/55983, l='MpServer', x=178.31, y=88.00, z=194.44], uu['Pig'/196, l='MpServer', x=211.53, y=80.00, z=217.50], uu['Pig'/193, l='MpServer', x=211.50, y=142.00, z=171.69], vq['item.item.slimeball'/56027, l='MpServer', x=181.16, y=121.13, z=193.72], uu['Pig'/195, l='MpServer', x=214.69, y=78.00, z=220.47], uu['Pig'/194, l='MpServer', x=208.50, y=87.00, z=205.50], vq['item.item.slimeball'/56005, l='MpServer', x=183.91, y=88.13, z=192.91], ws['Slime'/56000, l='MpServer', x=182.39, y=87.00, z=195.67], ws['Slime'/56001, l='MpServer', x=203.74, y=90.00, z=195.47], ws['Slime'/56002, l='MpServer', x=195.19, y=94.00, z=199.72], ws['Slime'/56003, l='MpServer', x=207.13, y=89.00, z=197.22], vq['item.item.slimeball'/56012, l='MpServer', x=164.66, y=144.13, z=170.03], ws['Slime'/56010, l='MpServer', x=195.70, y=93.00, z=194.31], vq['item.item.slimeball'/56036, l='MpServer', x=188.97, y=97.13, z=193.19], vq['item.item.slimeball'/56034, l='MpServer', x=189.19, y=113.13, z=199.72], vq['item.item.slimeball'/56032, l='MpServer', x=185.81, y=121.13, z=195.63]]
Retry entities: 0 total; []
Server brand: vanilla
Server type: Integrated singleplayer server
Stacktrace:
at bik.a(SourceFile:302)
at ays.b(SourceFile:1924)
at ays.e(SourceFile:720)
at net.minecraft.client.main.Main.main(SourceFile:103)

– System Details –
Details:
Minecraft Version: 13w41a
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.7.0_07, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 297157216 bytes (283 MB) / 579665920 bytes (552 MB) up to 3817799680 bytes (3640 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx4G
AABB Pool Size: 2086 (116816 bytes; 0 MB) allocated, 1024 (57344 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Launched Version: 13w41a
LWJGL: 2.9.0
OpenGL: Intel(R) HD Graphics GL version 2.1.0 - Build 8.15.10.2086, Intel
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: 1506 (84336 bytes; 0 MB) allocated, 200 (11200 bytes; 0 MB) used
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