I am the owner of the "Quick Quack" pack on twitch desktop client. I was trying to relase a new version for my modpack. Just after i launch minecraft, game crashes and it says AE2 is the potential cause of the problem.

Describe the bug
AE2 mod crashes the game after the launch.

To Reproduce
You need "Quick Quack" pack from CurseForge and these mods: AbyssalCraft, Advanced Inventory, Advanced Mortars, Advanced World Selection, AnimalNet, Apocalypse Dimension, Armor Toughness Bar, Chainmail Armor Crafting Recipe Mod, ChickenShed 1.1x, Chisel, ConnectedTexturesMod, Duck Craft, Controllable, DeathQuotes / Death Quotes, Draw Bridge, Ducky Mod, Environmental Tech, EverlastingAbilities, EverlastingAbilities-PotionCore, Potion Core, Giselbaer's Durability Viewer, Grid, Hunting Dimension, Item Got, Item Scroller, Just Enough Buttons, JustTheTips, Lightning Rods, Loot Slash Conquer, Modular Powersuits, MystAgrad Cloche Compat, Numina, Overloaded Armor Bar, Real Time Clock, RFTools, RFTools Dimensions, RFTools Power, Storage Tech, The Twilight Forest, Wesley's Roguelike Dungeons, YUNG's Better Caves, and all of the dependencies of the mods listed (The latest versions of the listed mods including beta versions relevant to this date: 3.November.2019) +OptiFine_1.12.2_HD_U_F4

Expected behavior
I expected the game to launch into the title screen.

Additional context
Crash Log: https://pastebin.com/pxXW2eQK

Environment
Java x64 Build 1.8.0_231-b11 ---- Windows 10
The latest versions of the above listed mods including beta versions relevant to this date: 3.November.2019

• Minecraft Version: 1.12.2
• AE2 Version: appliedenergistics2-rv6-stable-7
• Forge Version: forge-14.23.5.2847

Failed to register dimension for id 2, One is already registered

Your pack config seems broken some other mod is using the same dimension id as ae2

Thanks for your answer. You helped a lot. after you said same dimention id, i looked at my mod list and specified the mods adding dimentions into the game and tried them one by one. Apocalypse Dimension by aidencuneo v1.12.2_1.6 was causing it.

If you want to know start deleting mods or (if it is still a thing) just edit AE's dimension ID in config

@yueh i can yet not remember which mod (but i think it was one of the COFH mods) which could spit out all registered blockIDs, DimensionIDs and such info associated with the specific mod! Could the Exception, thrown here, be made more specific to tell which other mod is using the ID for easier config?