Crash loop on Mooshroom infusion

[HaraldKorneliussen]

Your GTNH Discord Username

No response

Mod Version

1.8.21

Bug Report

I tried to make a mooshroom using the vat, from a freshly cloned cow. When the infusion finished the world crashed, and kept crashing on reload. I did the same thing in a creative world, and confirmed the crash is there as well. Someting in TileVat.java craftingFinish leaves EntityLivingBase created as null.

Java Version

Other (Please Specify)

Mod List or GTNH Pack Version

Custom pack. Java version is 25.0.1. I thought first it might be ex futura adding the brown mooshroom causing it, but it still crashes with that mod unloaded. I have not tried removing any other mods (yet).

crash-2026-07-19_16.52.36-server.txt

Final Checklist

• I have searched the issues and haven't found a similar issue.

[HaraldKorneliussen]

I have now reproduced the issue with most mods disabled except Thaumcraft, NEI and the GTNH performance/fixes mods, crash log with mod list is appended.
I have also verified that it still crashes with a jarred cow (rather than one grown from a clone), and in Java 21.

crash-2026-07-19_19.55.30-server.txt

[HaraldKorneliussen]

I have found out that if I add a - in front of the ID in the recipe in ThaumicHorizons.java

critterRecipes.add(
                new CreatureInfusionRecipe(
                        "cowInfusion",
                        -EntityList.getEntityID(new EntityMooshroom(null)),
                        2,
                        (new AspectList()).add(Aspect.PLANT, 8).add(Aspect.BEAST, 4),
                        EntityCow.class,
                        new ItemStack[] { new ItemStack(Blocks.brown_mushroom), new ItemStack(Blocks.red_mushroom),
                                new ItemStack(Blocks.brown_mushroom), new ItemStack(Blocks.red_mushroom) },
                        0));

and add the presumably missing else block in the TileVat.java craftingFinish function (otherwise, even if it succeded in fetching a vanilla creature, it would immediately get overwritten):

public void craftingFinish(final Object out, final String label) {
        if (this.recipeType == 0) {
            if (out instanceof Integer) {
                EntityLivingBase created = null;
                if ((Integer) out < 0) {
                    created = (EntityLivingBase) EntityList.createEntityByID(-(Integer) out, this.worldObj);
                } else {
                    final ModContainer mc = Loader.instance().getIndexedModList().get("ThaumicHorizons");
                    try {
                        created = (EntityLivingBase) EntityRegistry.instance().lookupModSpawn(mc, (Integer) out)
                                .getEntityClass().getConstructor(World.class).newInstance(this.worldObj);
                    } catch (InvocationTargetException e) {
                        e.getCause().printStackTrace();
                    } catch (Exception e2) {
                        e2.printStackTrace();
                    }
                }

then a newly started infusion works. However, it doesn't save you if you're already in a crash loop unfortunately. To save my world I had to put a guard around the final assignment:

                if (created != null)
                {
                    created.copyLocationAndAnglesFrom(this.getEntityContained());
                    created.copyDataFrom(this.getEntityContained(), true);
                    if (created instanceof IEntityInfusedStats) {
                        ((IEntityInfusedStats) created).resetStats();
                    }
                    this.setEntityContained(created);
                }

and lost my mooshroom. I still have no idea how that happened, as such maybe you'd like to solve this in a better way, but in case you just want to use my fix I'll add a pull request.