Pixelmon 5.0 Beta 10 Crashing and cause people to disconnected when starting a battle

You need to provide the server console error.

Also having the same problem here is the attached crash report I was playing with roommate on LAN
---- Minecraft Crash Report ----
// Don't do that.

Time: 10/24/16 5:17 PM
Description: Rendering screen

java.lang.IllegalArgumentException: Illegal group reference: group index is missing
at java.util.regex.Matcher.appendReplacement(Unknown Source)
at java.util.regex.Matcher.replaceAll(Unknown Source)
at com.pixelmonmod.pixelmon.client.gui.battles.battleScreens.MainMenu.drawScreen(MainMenu.java:62)
at com.pixelmonmod.pixelmon.client.gui.battles.GuiBattle.func_73863_a(GuiBattle.java:484)
at net.minecraftforge.client.ForgeHooksClient.drawScreen(ForgeHooksClient.java:382)
at net.minecraft.client.renderer.EntityRenderer.func_181560_a(EntityRenderer.java:1094)
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1076)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:371)
at net.minecraft.client.main.Main.main(SourceFile:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)


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

-- Head --
Thread: Client thread
Stacktrace:
at java.util.regex.Matcher.appendReplacement(Unknown Source)
at java.util.regex.Matcher.replaceAll(Unknown Source)
at com.pixelmonmod.pixelmon.client.gui.battles.battleScreens.MainMenu.drawScreen(MainMenu.java:62)
at com.pixelmonmod.pixelmon.client.gui.battles.GuiBattle.func_73863_a(GuiBattle.java:484)
at net.minecraftforge.client.ForgeHooksClient.drawScreen(ForgeHooksClient.java:382)

-- Screen render details --
Details:
Screen name: com.pixelmonmod.pixelmon.client.gui.battles.GuiBattle
Mouse location: Scaled: (493, 479). Absolute: (987, 59)
Screen size: Scaled: (960, 509). Absolute: (1920, 1017). Scale factor of 2

-- Affected level --
Details:
Level name: MpServer
All players: 2 total; [EntityPlayerSP['tater_lover'/19, l='MpServer', x=9388.82, y=66.00, z=4310.22], EntityOtherPlayerMP['Bekaseka'/590, l='MpServer', x=9402.17, y=66.00, z=4308.29]]
Chunk stats: MultiplayerChunkCache: 439, 439
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (126,64,105), Chunk: (at 14,4,9 in 7,6; contains blocks 112,0,96 to 127,255,111), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 10078841 game time, 33655 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: 69 total; [EntityPixelmon['Goldeen'/2817, l='MpServer', x=9476.55, y=61.02, z=4345.47], EntityPixelmon['Shuckle'/2821, l='MpServer', x=9405.50, y=25.00, z=4340.50], EntityPixelmon['Chikorita'/2824, l='MpServer', x=9377.50, y=68.00, z=4262.50], NPCChatting[''/9, l='MpServer', x=9355.30, y=73.00, z=4251.30], EntityPixelmon['Diglett'/2828, l='MpServer', x=9370.50, y=12.00, z=4255.44], EntityItem['item.item.seeds'/1807, l='MpServer', x=9387.38, y=66.00, z=4313.97], NPCChatting[''/16, l='MpServer', x=9348.50, y=72.00, z=4247.70], EntityPixelmon['Shuckle'/2578, l='MpServer', x=9482.50, y=32.00, z=4308.50], EntityMinecartChest['Minecart with Chest'/22, l='MpServer', x=9346.50, y=12.06, z=4276.50], EntityCamera['unknown'/2070, l='MpServer', x=9386.00, y=68.00, z=4312.00], NPCShopkeeper[''/23, l='MpServer', x=9376.50, y=66.00, z=4230.50], EntityCamera['unknown'/2071, l='MpServer', x=9385.00, y=68.00, z=4307.00], NPCShopkeeper[''/24, l='MpServer', x=9376.50, y=66.00, z=4229.50], NPCChatting[''/25, l='MpServer', x=9353.48, y=70.00, z=4239.41], NPCChatting[''/27, l='MpServer', x=9345.29, y=72.00, z=4253.46], NPCChatting[''/29, l='MpServer', x=9356.50, y=70.00, z=4262.40], EntityPixelmon['Miltank'/2847, l='MpServer', x=9318.50, y=68.00, z=4219.50], EntityPixelmon['Tauros'/2592, l='MpServer', x=9417.59, y=64.00, z=4337.00], EntityPixelmon['Miltank'/2848, l='MpServer', x=9317.50, y=68.00, z=4218.50], EntityPixelmon['Miltank'/2850, l='MpServer', x=9317.93, y=67.00, z=4212.79], EntityPixelmon['Skiploom'/2851, l='MpServer', x=9320.50, y=68.00, z=4218.50], NPCNurseJoy[''/43, l='MpServer', x=9375.50, y=64.00, z=4272.50], EntityPlayerSP['tater_lover'/19, l='MpServer', x=9388.82, y=66.00, z=4310.22], EntityPixelmon['Typhlosion'/2862, l='MpServer', x=9388.81, y=66.00, z=4309.28], EntityPixelmon['Rattata'/2354, l='MpServer', x=9391.19, y=57.00, z=4342.46], EntityPixelmon['Diglett'/2634, l='MpServer', x=9403.50, y=54.00, z=4212.50], EntityOtherPlayerMP['Bekaseka'/590, l='MpServer', x=9402.17, y=66.00, z=4308.29], EntityOtherPlayerMP['Bekaseka'/590, l='MpServer', x=9402.17, y=66.00, z=4308.29], EntityItem['item.item.beetroot'/1615, l='MpServer', x=9388.19, y=67.94, z=4253.86], EntityItem['item.item.beetroot_seeds'/1617, l='MpServer', x=9386.19, y=67.00, z=4252.73], EntityPixelmon['Fearow'/2642, l='MpServer', x=9399.55, y=69.50, z=4337.16], EntityPixelmon['Magikarp'/2644, l='MpServer', x=9477.50, y=58.40, z=4338.50], EntityPixelmon['Goldeen'/2649, l='MpServer', x=9486.50, y=61.00, z=4343.50], EntityItem['item.item.seeds'/1884, l='MpServer', x=9402.89, y=65.00, z=4302.68], EntityItem['item.item.beetroot_seeds'/1118, l='MpServer', x=9388.46, y=67.94, z=4251.75], EntityItem['item.item.seeds'/1900, l='MpServer', x=9403.41, y=65.00, z=4304.11], EntityPixelmon['Spearow'/2418, l='MpServer', x=9436.17, y=63.00, z=4337.02], EntityPixelmon['Aron'/2693, l='MpServer', x=9415.50, y=57.00, z=4285.50], EntityPixelmon['Aron'/2694, l='MpServer', x=9416.50, y=57.00, z=4285.50], EntityPixelmon['Arbok'/2701, l='MpServer', x=9436.89, y=76.00, z=4214.84], EntityPixelmon['Voltorb'/2702, l='MpServer', x=9423.88, y=68.00, z=4274.09], EntityPixelmon['Pidgeotto'/2454, l='MpServer', x=9371.42, y=64.00, z=4278.47], EntityItem['item.item.seeds'/1947, l='MpServer', x=9386.20, y=65.00, z=4305.05], EntityItem['item.item.beetroot'/1439, l='MpServer', x=9386.68, y=67.00, z=4252.92], EntityItem['item.item.beetroot_seeds'/1441, l='MpServer', x=9388.20, y=67.94, z=4252.78], EntityPixelmon['Staravia'/2721, l='MpServer', x=9401.50, y=74.50, z=4332.12], EntityPixelmon['Pidgey'/2476, l='MpServer', x=9344.21, y=72.00, z=4247.78], EntityPixelmon['Shuckle'/2732, l='MpServer', x=9446.50, y=36.00, z=4259.50], EntityItem['item.item.beetroot'/686, l='MpServer', x=9387.73, y=67.94, z=4249.72], EntityPixelmon['Skarmory'/2735, l='MpServer', x=9403.69, y=65.00, z=4308.29], EntityPixelmon['Dugtrio'/2486, l='MpServer', x=9417.50, y=57.00, z=4284.50], EntityPixelmon['Hoppip'/2746, l='MpServer', x=9476.71, y=64.00, z=4401.39], EntityPixelmon['Hoppip'/2747, l='MpServer', x=9480.76, y=63.00, z=4386.50], EntityPixelmon['Aron'/2752, l='MpServer', x=9340.50, y=17.00, z=4292.50], EntityPixelmon['Bayleef'/2754, l='MpServer', x=9412.57, y=66.00, z=4211.75], EntityPixelmon['Shuckle'/2755, l='MpServer', x=9357.50, y=9.00, z=4333.50], EntityPixelmon['Kadabra'/2758, l='MpServer', x=9482.50, y=64.00, z=4303.50], EntityPixelmon['Hoppip'/2766, l='MpServer', x=9289.50, y=67.00, z=4266.50], EntityPixelmon['Togetic'/2767, l='MpServer', x=9294.50, y=67.00, z=4268.50], EntityPixelmon['Dugtrio'/2768, l='MpServer', x=9474.50, y=56.00, z=4322.50], EntityPixelmon['Solrock'/2517, l='MpServer', x=9415.28, y=33.00, z=4265.94], EntityPixelmon['Rattata'/2773, l='MpServer', x=9382.11, y=64.00, z=4370.50], EntityPixelmon['Rattata'/2775, l='MpServer', x=9382.50, y=64.00, z=4367.50], EntityPixelmon['Shuckle'/2777, l='MpServer', x=9468.50, y=31.00, z=4322.41], EntityPixelmon['Pidgey'/2523, l='MpServer', x=9359.28, y=68.10, z=4408.36], EntityPixelmon['Weepinbell'/2791, l='MpServer', x=9458.50, y=68.00, z=4282.50], EntityPixelmon['Pidgey'/2792, l='MpServer', x=9446.72, y=65.00, z=4272.86], EntityPixelmon['Diglett'/2808, l='MpServer', x=9473.50, y=17.00, z=4317.50], EntityPixelmon['Dugtrio'/2809, l='MpServer', x=9338.50, y=55.00, z=4356.50]]
Retry entities: 0 total; []
Server brand: fml,forge
Server type: Integrated singleplayer server
Stacktrace:
at net.minecraft.client.multiplayer.WorldClient.func_72914_a(WorldClient.java:415)
at net.minecraft.client.Minecraft.func_71396_d(Minecraft.java:2660)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:392)
at net.minecraft.client.main.Main.main(SourceFile:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

-- System Details --
Details:
Minecraft Version: 1.10.2
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_112, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1647835872 bytes (1571 MB) / 3093299200 bytes (2950 MB) up to 6105333760 bytes (5822 MB)
JVM Flags: 4 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -XX:MaxPermSize=128m -Xmx6549M -Xms256M
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
FML: MCP 9.32 Powered by Forge 12.18.1.2075 4 mods loaded, 4 mods active
States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored
UCHIJAAAA mcp{9.19} [Minecraft Coder Pack] (minecraft.jar)
UCHIJAAAA FML{8.0.99.99} [Forge Mod Loader] (forge-1.10.2-12.18.1.2075.jar)
UCHIJAAAA Forge{12.18.1.2075} [Minecraft Forge] (forge-1.10.2-12.18.1.2075.jar)
UCHIJAAAA pixelmon{5.0.0-beta9} [Pixelmon] (Pixelmon-1.10.2-5.0.0-beta9-universal.jar)
Loaded coremods (and transformers):
GL info: ' Vendor: 'NVIDIA Corporation' Version: '4.5.0 NVIDIA 369.09' Renderer: 'GeForce GTX 970/PCIe/SSE2'
Launched Version: 1.10.2-forge1.10.2-12.18.1.2075
LWJGL: 2.9.4
OpenGL: GeForce GTX 970/PCIe/SSE2 GL version 4.5.0 NVIDIA 369.09, 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: Yes
Is Modded: Definitely; Client brand changed to 'fml,forge'
Type: Client (map_client.txt)
Resource Packs:
Current Language: English (US)
Profiler Position: N/A (disabled)
CPU: 8x Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz

Does your battling Pokémon have a nickname? If so, what is it?

Almost everybody is nicknamed
Goldem(Shiny Golem)
Ty$(Typhlosion)
Pidgebro(Pidgeot)
and then a revolving cast of others.
I haven't paid attention to who is doing it worse :(

I reset my typhlosion's name and no crash then I battle with the ty$ nickname and it crashed.
So thank you I don't know why I wasn't recognizing that is what was doing it before

Closed as it's expired and resolved