Description of the issue:

Crashed on startup. not much to say.

Crashlog:

---- Minecraft Crash Report ----

WARNING: coremods are present:
Inventory Tweaks Coremod (InventoryTweaks-1.63.jar)
IELoadingPlugin (ImmersiveEngineering-core-0.12-85.jar)
Contact their authors BEFORE contacting forge

// Why did you do that?

Time: 10/5/18 4:24 PM
Description: There was a severe problem during mod loading that has caused the game to fail

net.minecraftforge.fml.common.LoaderExceptionModCrash: Caught exception from Immersive Engineering (immersiveengineering)
Caused by: java.lang.IllegalAccessError: tried to access class net.minecraft.potion.PotionHelper$MixPredicate from class blusunrize.immersiveengineering.common.IEContent
at blusunrize.immersiveengineering.common.IEContent.postInit(IEContent.java:1014)
at blusunrize.immersiveengineering.ImmersiveEngineering.postInit(ImmersiveEngineering.java:145)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraftforge.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:624)
at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.Subscriber.invokeSubscriberMethod(Subscriber.java:91)
at com.google.common.eventbus.Subscriber$SynchronizedSubscriber.invokeSubscriberMethod(Subscriber.java:150)
at com.google.common.eventbus.Subscriber$1.run(Subscriber.java:76)
at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:399)
at com.google.common.eventbus.Subscriber.dispatchEvent(Subscriber.java:71)
at com.google.common.eventbus.Dispatcher$PerThreadQueuedDispatcher.dispatch(Dispatcher.java:116)
at com.google.common.eventbus.EventBus.post(EventBus.java:217)
at net.minecraftforge.fml.common.LoadController.sendEventToModContainer(LoadController.java:218)
at net.minecraftforge.fml.common.LoadController.propogateStateMessage(LoadController.java:196)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.Subscriber.invokeSubscriberMethod(Subscriber.java:91)
at com.google.common.eventbus.Subscriber$SynchronizedSubscriber.invokeSubscriberMethod(Subscriber.java:150)
at com.google.common.eventbus.Subscriber$1.run(Subscriber.java:76)
at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:399)
at com.google.common.eventbus.Subscriber.dispatchEvent(Subscriber.java:71)
at com.google.common.eventbus.Dispatcher$PerThreadQueuedDispatcher.dispatch(Dispatcher.java:116)
at com.google.common.eventbus.EventBus.post(EventBus.java:217)
at net.minecraftforge.fml.common.LoadController.distributeStateMessage(LoadController.java:135)
at net.minecraftforge.fml.common.Loader.initializeMods(Loader.java:749)
at net.minecraftforge.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:336)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:534)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:377)
at net.minecraft.client.main.Main.main(SourceFile:123)
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:

-- System Details --
Details:
Minecraft Version: 1.12.2
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_172, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 622493120 bytes (593 MB) / 1857552384 bytes (1771 MB) up to 11453595648 bytes (10923 MB)
JVM Flags: 4 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx12288m -Xms256m -XX:PermSize=256m
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
FML: MCP 9.42 Powered by Forge 14.23.5.2768 14 mods loaded, 14 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                                |
|:------ |:-------------------- |:------------------------ |:----------------------------------- |:---------------------------------------- |
| UCHIJ  | minecraft            | 1.12.2                   | minecraft.jar                       | None                                     |
| UCHIJ  | mcp                  | 9.42                     | minecraft.jar                       | None                                     |
| UCHIJ  | FML                  | 8.0.99.99                | forge-1.12.2-14.23.5.2768.jar       | e3c3d50c7c986df74c645c0ac54639741c90a557 |
| UCHIJ  | forge                | 14.23.5.2768             | forge-1.12.2-14.23.5.2768.jar       | e3c3d50c7c986df74c645c0ac54639741c90a557 |
| UCHIJ  | buildinggadgets      | 1.6.2                    | BuildingGadgets-1.6.2.jar           | None                                     |
| UCHIJ  | jei                  | 4.12.1.217               | jei_1.12.2-4.12.1.217.jar           | None                                     |
| UCHIJ  | forestry             | 5.8.1.322                | forestry_1.12.2-5.8.1.322.jar       | None                                     |
| UCHIJ  | gravestone           | 1.10.1                   | gravestone-1.10.1.jar               | None                                     |
| UCHIEE | immersiveengineering | 0.12-85                  | ImmersiveEngineering-0.12-85.jar    | 4cb49fcde3b43048c9889e0a3d083225da926334 |
| UCHI   | immersivecables      | 1.3.2                    | ImmersiveCables-1.12.2-1.3.2.jar    | None                                     |
| UCHI   | immersivepetroleum   | 1.1.9                    | immersivepetroleum-1.12.2-1.1.9.jar | None                                     |
| UCHI   | immersivetech        | 1.3.10                   | immersivetech-1.12-1.3.10.jar       | None                                     |
| UCHI   | inventorytweaks      | 1.63+release.109.220f184 | InventoryTweaks-1.63.jar            | 55d2cd4f5f0961410bf7b91ef6c6bf00a766dcbe |
| UCHI   | trackapi             | 1.1                      | TrackAPI-1.1_1.12.jar               | None                                     |

Loaded coremods (and transformers): 

Inventory Tweaks Coremod (InventoryTweaks-1.63.jar)
invtweaks.forge.asm.ContainerTransformer
IELoadingPlugin (ImmersiveEngineering-core-0.12-85.jar)
blusunrize.immersiveengineering.common.asm.IEClassTransformer
GL info: ' Vendor: 'NVIDIA Corporation' Version: '4.6.0 NVIDIA 398.36' Renderer: 'GeForce GTX 1060 6GB/PCIe/SSE2'

Versions & Modlist

Minecraft version 1.12.2
All other info in this screenshot

did it help?

if yes what version did you take

Im getting the same thing xD

Downgrade forge, they changed the potion registry without notice

Thanks!