Annoying Crash

Whenever I load a world in minecraft 1.7.2 forge this crash comes up (this crash is new btw I didn't have all the other times in 1.7.2 Forge.

---- Minecraft Crash Report ----
// I feel sad now

Time: 7/8/14 8:43 AM
Description: Exception in server tick loop

java.lang.NullPointerException: Exception in server tick loop
at drzhark.customspawner.handlers.SpawnTickHandler.worldTick(SpawnTickHandler.java:26)
at cpw.mods.fml.common.eventhandler.ASMEventHandler_60_SpawnTickHandler_worldTick_WorldTickEvent.invoke(.dynamic)
at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:51)
at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:122)
at cpw.mods.fml.common.FMLCommonHandler.onPreWorldTick(FMLCommonHandler.java:258)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:641)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:568)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:185)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:452)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:705)


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

-- System Details --
Details:
Minecraft Version: 1.7.2
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.7.0_55, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 150222560 bytes (143 MB) / 511705088 bytes (488 MB) up to 954728448 bytes (910 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 13, tcache: 0, allocated: 13, tallocated: 95
FML: MCP v9.01-pre FML v7.2.116.1024 Minecraft Forge 10.12.0.1024 Optifine OptiFine_1.7.2_HD_U_C2 13 mods loaded, 13 mods active
mcp{8.09} [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
FML{7.2.116.1024} [Forge Mod Loader] (forge-1.7.2-10.12.0.1024.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Forge{10.12.0.1024} [Minecraft Forge] (forge-1.7.2-10.12.0.1024.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
TooManyItems{1.7.2} [TooManyItems] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
DamageIndicatorsMod{3.0.5} [Damage Indicators] ([1.7.2]DamageIndicatorsMod-3.0.5.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
ArrowCamMod{2.0.0} [Arrow Cam Mod] (ArrowCamMod-1.7.2-2.0.0.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
XaeroBetterPvP{1.0.8} [Better PVP Mod] (BetterPvP_1.0.8_1.7.2_Forge.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BiomesOPlenty{2.0.0} [Biomes O' Plenty] (BiomesOPlenty-1.7.2-2.0.0.750-universal.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
CustomSpawner{3.2.0.dev.R1} [DrZhark's CustomSpawner] (CustomMobSpawner 3.2.0-DEV-R2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
customnpcs{1.7.2} [CustomNpcs] (CustomNPCs_1.7.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
MoCreatures{6.2.0.dev.R1} [DrZhark's Mo'Creatures Mod] (DrZharks MoCreatures Mod v6.2.0-DEV-R2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
mccapesextra{1.7.2a} [MCCapes Extra] (MCCapesExtra_1.7.2a.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
voxelmap{1.7.2} [VoxelMap] (voxelmap-1.7.2-1.0.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Profiler Position: N/A (disabled)
Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Player Count: 0 / 8; []
Type: Integrated Server (map_client.txt)
Is Modded: Definitely; Client brand changed to 'fml,forge'