I was trying to get to a ladder when there was an invisible ladder in my way (so I thought!) and then once I broke it, it broke the ladder on the wall. Upon trying to replace the ladder I immediately crashed, in SinglePlayer and on a server.

Minecraft Crash report:

---- Minecraft Crash Report ----
// Sorry

Time: 09/07/14 5:30 PM
Description: Unexpected error

java.lang.IllegalArgumentException: Cannot get property bck

as it does not exist!
at bbw.b(SourceFile:91)
at avi.a(SourceFile:47)
at avi.a(SourceFile:35)
at apm.a(SourceFile:2320)
at ait.a(SourceFile:106)
at cdt.a(SourceFile:295)
at bqi.ar(SourceFile:1325)
at bqi.q(SourceFile:1682)
at bqi.ap(SourceFile:863)
at bqi.a(SourceFile:303)
at net.minecraft.client.main.Main.main(SourceFile:120)

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

– Head –
Stacktrace:
at bbw.b(SourceFile:91)
at avi.a(SourceFile:47)
at avi.a(SourceFile:35)
at apm.a(SourceFile:2320)
at ait.a(SourceFile:106)
at cdt.a(SourceFile:295)
at bqi.ar(SourceFile:1325)

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [chv['cowteal'/233, l='MpServer', x=-212.23, y=67.00, z=142.94]]
Chunk stats: MultiplayerChunkCache: 625, 625
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: -214.00,68.00,178.00 - World: (-214,68,178), Chunk: (at 10,4,2 in -14,11; contains blocks -224,0,176 to -209,255,191), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 120482258 game time, 124496290 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: survival (ID 0). Hardcore: false. Cheats: false
Forced entities: 117 total; [adr['Creeper'/43, l='MpServer', x=-291.56, y=19.00, z=147.03], afk['Zombie'/49, l='MpServer', x=-288.34, y=21.00, z=213.00], abb['Bat'/55, l='MpServer', x=-281.78, y=13.95, z=208.84], adr['Creeper'/54, l='MpServer', x=-279.56, y=14.00, z=205.94], aex['Skeleton'/53, l='MpServer', x=-280.53, y=15.00, z=198.84], afk['Zombie'/52, l='MpServer', x=-276.47, y=23.00, z=122.94], adr['Creeper'/59, l='MpServer', x=-280.25, y=20.00, z=217.66], adr['Creeper'/58, l='MpServer', x=-283.63, y=18.00, z=214.69], afk['Zombie'/57, l='MpServer', x=-275.97, y=24.00, z=208.50], adr['Creeper'/56, l='MpServer', x=-285.41, y=12.00, z=208.97], afk['Zombie'/62, l='MpServer', x=-277.13, y=20.00, z=218.47], adr['Creeper'/61, l='MpServer', x=-286.09, y=22.00, z=211.34], afk['Zombie'/60, l='MpServer', x=-278.56, y=21.00, z=218.09], afk['Zombie'/68, l='MpServer', x=-272.22, y=22.00, z=134.69], afk['Zombie'/69, l='MpServer', x=-270.50, y=22.00, z=134.50], abb['Bat'/70, l='MpServer', x=-256.81, y=34.10, z=128.38], aex['Skeleton'/71, l='MpServer', x=-259.78, y=34.00, z=168.94], abw['Sheep'/66, l='MpServer', x=-264.94, y=70.00, z=98.06], abb['Bat'/67, l='MpServer', x=-261.25, y=20.10, z=120.25], abb['Bat'/73, l='MpServer', x=-263.27, y=13.75, z=219.26], afk['Zombie'/74, l='MpServer', x=-269.47, y=22.00, z=220.28], abb['Bat'/75, l='MpServer', x=-270.38, y=22.10, z=219.88], wt['Experience Orb'/95, l='MpServer', x=-253.22, y=12.00, z=216.37], abn['Pig'/89, l='MpServer', x=-255.59, y=73.00, z=67.28], adr['Creeper'/102, l='MpServer', x=-225.03, y=19.00, z=124.59], afk['Zombie'/100, l='MpServer', x=-233.50, y=35.00, z=94.50], aff['Spider'/101, l='MpServer', x=-232.50, y=22.00, z=118.50], adr['Creeper'/110, l='MpServer', x=-220.53, y=26.00, z=153.25], aex['Skeleton'/111, l='MpServer', x=-214.50, y=28.00, z=155.13], afk['Zombie'/108, l='MpServer', x=-214.56, y=20.00, z=143.06], afk['Zombie'/109, l='MpServer', x=-211.97, y=18.00, z=131.44], aex['Skeleton'/106, l='MpServer', x=-220.25, y=25.00, z=143.09], afk['Zombie'/107, l='MpServer', x=-219.63, y=21.00, z=130.03], aex['Skeleton'/105, l='MpServer', x=-213.94, y=21.00, z=131.53], aex['Skeleton'/119, l='MpServer', x=-219.19, y=21.00, z=162.25], ww['entity.ItemFrame.name'/118, l='MpServer', x=-219.97, y=73.50, z=148.50], ww['entity.ItemFrame.name'/117, l='MpServer', x=-219.97, y=72.50, z=148.50], ww['entity.ItemFrame.name'/116, l='MpServer', x=-219.97, y=71.50, z=148.50], ww['entity.ItemFrame.name'/115, l='MpServer', x=-219.97, y=73.50, z=153.50], ww['entity.ItemFrame.name'/114, l='MpServer', x=-219.97, y=72.50, z=153.50], ww['entity.ItemFrame.name'/113, l='MpServer', x=-219.97, y=71.50, z=153.50], aex['Skeleton'/112, l='MpServer', x=-220.50, y=20.00, z=149.06], aff['Spider'/127, l='MpServer', x=-197.75, y=27.00, z=116.31], adr['Creeper'/123, l='MpServer', x=-213.94, y=23.00, z=220.34], aex['Skeleton'/122, l='MpServer', x=-217.41, y=24.00, z=215.94], aex['Skeleton'/121, l='MpServer', x=-216.34, y=21.00, z=213.72], aex['Skeleton'/120, l='MpServer', x=-218.31, y=22.00, z=165.63], abb['Bat'/136, l='MpServer', x=-194.88, y=48.10, z=216.53], ww['entity.ItemFrame.name'/141, l='MpServer', x=-195.03, y=63.50, z=225.50], ww['entity.ItemFrame.name'/143, l='MpServer', x=-205.97, y=64.50, z=234.50], ww['entity.ItemFrame.name'/142, l='MpServer', x=-205.97, y=63.50, z=225.50], ww['entity.ItemFrame.name'/129, l='MpServer', x=-203.03, y=72.50, z=144.50], ww['entity.ItemFrame.name'/128, l='MpServer', x=-203.03, y=73.50, z=144.50], ww['entity.ItemFrame.name'/131, l='MpServer', x=-203.03, y=71.50, z=149.50], ww['entity.ItemFrame.name'/130, l='MpServer', x=-203.03, y=71.50, z=144.50], ww['entity.ItemFrame.name'/133, l='MpServer', x=-203.03, y=73.50, z=149.50], ww['entity.ItemFrame.name'/132, l='MpServer', x=-203.03, y=72.50, z=149.50], abb['Bat'/135, l='MpServer', x=-202.25, y=25.10, z=222.56], aex['Skeleton'/134, l='MpServer', x=-206.94, y=27.00, z=216.72], aex['Skeleton'/152, l='MpServer', x=-178.75, y=26.00, z=178.28], aex['Skeleton'/153, l='MpServer', x=-179.72, y=26.00, z=179.06], abb['Bat'/154, l='MpServer', x=-172.45, y=27.71, z=184.15], ww['entity.ItemFrame.name'/144, l='MpServer', x=-195.50, y=64.50, z=224.03], ww['entity.ItemFrame.name'/145, l='MpServer', x=-205.50, y=64.50, z=224.03], ww['entity.ItemFrame.name'/146, l='MpServer', x=-195.03, y=64.50, z=234.50], ww['entity.ItemFrame.name'/147, l='MpServer', x=-205.97, y=64.50, z=229.50], ww['entity.ItemFrame.name'/148, l='MpServer', x=-195.03, y=64.50, z=229.50], aex['Skeleton'/151, l='MpServer', x=-177.84, y=26.00, z=183.50], abf['Cow'/171, l='MpServer', x=-163.00, y=68.00, z=116.03], abf['Cow'/170, l='MpServer', x=-166.94, y=68.00, z=114.63], abf['Cow'/169, l='MpServer', x=-165.75, y=68.00, z=115.06], abf['Cow'/168, l='MpServer', x=-165.97, y=68.00, z=111.44], abf['Cow'/175, l='MpServer', x=-160.31, y=68.00, z=115.44], abf['Cow'/174, l='MpServer', x=-163.16, y=68.00, z=113.66], abf['Cow'/173, l='MpServer', x=-164.44, y=68.00, z=112.53], abf['Cow'/172, l='MpServer', x=-159.13, y=68.00, z=117.44], abf['Cow'/163, l='MpServer', x=-155.63, y=68.00, z=109.84], abf['Cow'/162, l='MpServer', x=-164.53, y=68.00, z=109.06], abf['Cow'/161, l='MpServer', x=-166.94, y=68.00, z=109.06], abf['Cow'/167, l='MpServer', x=-166.94, y=68.00, z=110.22], abf['Cow'/166, l='MpServer', x=-163.38, y=68.00, z=111.22], abf['Cow'/165, l='MpServer', x=-164.72, y=68.00, z=111.34], abf['Cow'/164, l='MpServer', x=-165.66, y=68.00, z=110.09], abf['Cow'/187, l='MpServer', x=-152.09, y=68.00, z=109.06], abf['Cow'/190, l='MpServer', x=-154.34, y=68.00, z=109.06], abf['Cow'/191, l='MpServer', x=-152.41, y=68.00, z=111.63], abf['Cow'/188, l='MpServer', x=-153.22, y=68.00, z=109.06], abf['Cow'/189, l='MpServer', x=-152.09, y=68.00, z=110.34], abb['Bat'/178, l='MpServer', x=-174.78, y=26.68, z=179.10], abb['Bat'/179, l='MpServer', x=-164.47, y=13.10, z=195.06], aex['Skeleton'/176, l='MpServer', x=-171.69, y=26.00, z=186.16], abb['Bat'/177, l='MpServer', x=-178.94, y=27.01, z=181.24], abf['Cow'/205, l='MpServer', x=-152.09, y=68.00, z=115.94], abf['Cow'/204, l='MpServer', x=-159.06, y=68.00, z=115.00], abf['Cow'/207, l='MpServer', x=-152.09, y=68.00, z=114.81], abf['Cow'/206, l='MpServer', x=-157.22, y=68.00, z=116.44], abf['Cow'/201, l='MpServer', x=-153.22, y=68.00, z=118.91], abf['Cow'/200, l='MpServer', x=-154.50, y=68.00, z=116.63], abf['Cow'/203, l='MpServer', x=-154.41, y=68.00, z=118.91], abf['Cow'/202, l='MpServer', x=-153.41, y=68.00, z=117.44], abf['Cow'/197, l='MpServer', x=-163.84, y=68.00, z=118.91], abf['Cow'/196, l='MpServer', x=-161.88, y=68.00, z=116.53], abf['Cow'/199, l='MpServer', x=-153.94, y=68.00, z=113.28], abf['Cow'/198, l='MpServer', x=-152.09, y=68.00, z=118.91], abf['Cow'/193, l='MpServer', x=-153.38, y=68.00, z=110.31], abf['Cow'/192, l='MpServer', x=-155.34, y=68.00, z=112.63], abf['Cow'/195, l='MpServer', x=-156.72, y=68.00, z=111.22], abf['Cow'/194, l='MpServer', x=-154.53, y=68.00, z=111.47], abf['Cow'/212, l='MpServer', x=-153.25, y=68.00, z=116.06], abf['Cow'/213, l='MpServer', x=-157.97, y=68.00, z=118.91], abf['Cow'/214, l='MpServer', x=-161.88, y=68.00, z=109.91], afk['Zombie'/215, l='MpServer', x=-134.47, y=17.00, z=91.03], abf['Cow'/208, l='MpServer', x=-152.13, y=68.00, z=117.72], abf['Cow'/209, l='MpServer', x=-153.31, y=68.00, z=114.47], abf['Cow'/210, l='MpServer', x=-159.38, y=68.00, z=118.91], abf['Cow'/211, l='MpServer', x=-156.22, y=68.00, z=115.09], chv['cowteal'/233, l='MpServer', x=-212.23, y=67.00, z=142.94]]
Retry entities: 0 total; []
Server brand: vanilla
Server type: Integrated singleplayer server
Stacktrace:
at cdu.a(SourceFile:308)
at bqi.b(SourceFile:2139)
at bqi.a(SourceFile:317)
at net.minecraft.client.main.Main.main(SourceFile:120)

– System Details –
Details:
Minecraft Version: 14w28a
Operating System: Windows 8 (amd64) version 6.2
Java Version: 1.7.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 436383328 bytes (416 MB) / 1051197440 bytes (1002 MB) up to 3817865216 bytes (3641 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx4G
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Launched Version: 14w28a
LWJGL: 2.9.1
OpenGL: GeForce GT 740M/PCIe/SSE2 GL version 4.3.0, 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.

Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: [faithful32pack.zip]
Current Language: Canadian English (Canada)
Profiler Position: N/A (disabled)