Crash Report:
---- Minecraft Crash Report ----
// You should try our sister game, Minceraft!

Time: 8/4/15 10:26 AM
Description: Ticking entity

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Random.java:250)
	at acf.a(SourceFile:94)
	at ack$a.a(SourceFile:217)
	at ack.a(SourceFile:121)
	at ack.a(SourceFile:128)
	at ack.b(SourceFile:227)
	at wq.t_(SourceFile:303)
	at adm.a(SourceFile:1408)
	at le.a(SourceFile:597)
	at adm.g(SourceFile:1386)
	at adm.i(SourceFile:1279)
	at le.i(SourceFile:478)
	at net.minecraft.server.MinecraftServer.B(SourceFile:607)
	at net.minecraft.server.MinecraftServer.A(SourceFile:535)
	at bpo.A(SourceFile:152)
	at net.minecraft.server.MinecraftServer.run(SourceFile:451)
	at java.lang.Thread.run(Thread.java:695)


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

-- Head --
Stacktrace:
	at java.util.Random.nextInt(Random.java:250)
	at acf.a(SourceFile:94)
	at ack$a.a(SourceFile:217)
	at ack.a(SourceFile:121)
	at ack.a(SourceFile:128)
	at ack.b(SourceFile:227)
	at wq.t_(SourceFile:303)
	at adm.a(SourceFile:1408)
	at le.a(SourceFile:597)
	at adm.g(SourceFile:1386)

-- Entity being ticked --
Details:
	Entity Type: Arrow (wq)
	Entity ID: 754610
	Entity Name: Arrow
	Entity's Exact location: 443.97, 68.03, 923.05
	Entity's Block location: 443.00,68.00,923.00 - World: (443,68,923), Chunk: (at 11,4,11 in 27,57; contains blocks 432,0,912 to 447,255,927), Region: (0,1; contains chunks 0,32 to 31,63, blocks 0,0,512 to 511,255,1023)
	Entity's Momentum: 1.25, -0.32, 1.61
	Entity's Rider: ~~ERROR~~ NullPointerException: null
	Entity's Vehicle: ~~ERROR~~ NullPointerException: null
Stacktrace:
	at adm.i(SourceFile:1279)
	at le.i(SourceFile:478)

-- Affected level --
Details:
	Level name: Survival
	All players: 1 total; [lf['JohnFsonic'/326589, l='Survival', x=441.56, y=67.00, z=919.68]]
	Chunk stats: ServerChunkCache: 937 Drop: 0
	Level seed: -7497688943371679744
	Level generator: ID 08 - default_1_1, ver 0. Features enabled: true
	Level generator options: 
	Level spawn location: 32.00,64.00,-128.00 - World: (32,64,-128), Chunk: (at 0,4,0 in 2,-8; contains blocks 32,0,-128 to 47,255,-113), Region: (0,-1; contains chunks 0,-32 to 31,-1, blocks 0,0,-512 to 511,255,-1)
	Level time: 478983 game time, 13814 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 108742 (now: false), thunder time: 131698 (now: false)
	Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.server.MinecraftServer.B(SourceFile:607)
	at net.minecraft.server.MinecraftServer.A(SourceFile:535)
	at bpo.A(SourceFile:152)
	at net.minecraft.server.MinecraftServer.run(SourceFile:451)
	at java.lang.Thread.run(Thread.java:695)

-- System Details --
Details:
	Minecraft Version: 1.8.8
	Operating System: Mac OS X (x86_64) version 10.10.3
	Java Version: 1.6.0_65, Apple Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
	Memory: 305677232 bytes (291 MB) / 671199232 bytes (640 MB) up to 1060372480 bytes (1011 MB)
	JVM Flags: 5 total; -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
	IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
	Profiler Position: N/A (disabled)
	Player Count: 1 / 8; [lf['JohnFsonic'/326589, l='Survival', x=441.56, y=67.00, z=919.68]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.