Minecraft will no longer create or load worlds (It always crashes) after configuring Pixelmon

A detailed walkthrough of the error, its code path and all known details is as follows:
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-- Head --
Thread: Server thread
Stacktrace:
    at com.pixelmonmod.pixelmon.enums.EnumSpecies.getFromNameAnyCaseNoTranslate(EnumSpecies.java:1364)
    at com.pixelmonmod.pixelmon.config.StarterList.getStarterList(StarterList.java:57)
    at com.pixelmonmod.pixelmon.comm.packetHandlers.StarterListPacket.<init>(StarterListPacket.java:24)
    at com.pixelmonmod.pixelmon.TickHandler.registerStarterList(TickHandler.java:181)
    at com.pixelmonmod.pixelmon.storage.ReforgedStorageManager.getParty(ReforgedStorageManager.java:88)
    at com.pixelmonmod.pixelmon.api.storage.IStorageManager.getParty(IStorageManager.java:37)
    at com.pixelmonmod.pixelmon.listener.PixelmonPlayerTracker.onPlayerLogin(PixelmonPlayerTracker.java:48)
    at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_81_PixelmonPlayerTracker_onPlayerLogin_PlayerLoggedInEvent.invoke(.dynamic)
    at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90)
    at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:182)
    at net.minecraftforge.fml.common.FMLCommonHandler.firePlayerLoggedIn(FMLCommonHandler.java:575)
    at net.minecraft.server.management.PlayerList.initializeConnectionToPlayer(PlayerList.java:219)
    at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher.completeServerSideConnection(NetworkDispatcher.java:255)
    at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher.access$100(NetworkDispatcher.java:72)
    at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher$1.func_73660_a(NetworkDispatcher.java:205)
    at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:285)

-- Ticking connection --
Details:
    Connection: net.minecraft.network.NetworkManager@36b2e70a
Stacktrace:
    at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:180)
    at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:790)
    at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:668)
    at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:185)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526)
    at java.lang.Thread.run(Thread.java:745)

-- System Details --
Details:
    Minecraft Version: 1.12.2
    Operating System: Windows 10 (amd64) version 10.0
    Java Version: 1.8.0_51, Oracle Corporation
    Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
    Memory: 1088266584 bytes (1037 MB) / 1577058304 bytes (1504 MB) up to 2147483648 bytes (2048 MB)
    JVM Flags: 8 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
    IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
    FML: MCP 9.42 Powered by Forge 14.23.5.2854 5 mods loaded, 5 mods active
    States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored

    | State  | ID        | Version      | Source                              | Signature                                |
    |:------ |:--------- |:------------ |:----------------------------------- |:---------------------------------------- |
    | LCHIJA | minecraft | 1.12.2       | minecraft.jar                       | None                                     |
    | LCHIJA | mcp       | 9.42         | minecraft.jar                       | None                                     |
    | LCHIJA | FML       | 8.0.99.99    | forge-1.12.2-14.23.5.2854.jar       | e3c3d50c7c986df74c645c0ac54639741c90a557 |
    | LCHIJA | forge     | 14.23.5.2854 | forge-1.12.2-14.23.5.2854.jar       | e3c3d50c7c986df74c645c0ac54639741c90a557 |
    | LCHIJA | pixelmon  | 8.1.2        | Pixelmon-1.12.2-8.1.2-universal.jar | None                                     |

    Loaded coremods (and transformers): 
    GL info: ~~ERROR~~ RuntimeException: No OpenGL context found in the current thread.
    Profiler Position: N/A (disabled)
    Player Count: 1 / 8; [EntityPlayerMP['SlySushi'/198, l='New World', x=-95.50, y=76.00, z=96.50]]
    Type: Integrated Server (map_client.txt)
    Is Modded: Definitely; Client brand changed to 'fml,forge'