Draco18s

Post the whole class.

Without seeing your whole code, I can only make guesses. You also didn't post the error, just the line that caused it.

This is probably because mov.entityHit is null. You should check for that. Yes. @EventHandler is for FML mod lifecycle events.

Why do you have both @SubscribeEvent and @EventHandler?

If you have a reason to extend the diode, sure.

Do you have this anywhere: @SubscribeEvent public void onEvent(MouseEvent event) { //... }

That's effectively a library mod. "Coremod" has a specific meaning.

Welp, there's your problem. You're not supposed to extend the event classes. You're supposed to create a single function that takes a single parameter (of any Event subtype) and mark it with an @EventHandler annotation. Can you please link the tutorial you were using?

Registry name is per block, not per state. You can only set it once.

Your TileEntity's NBT methods aren't calling super, ergo there is some data loss (the TE's position in the world), and rather than try and recover what it can (because it doesn't know where it goes), Minecraft just creates a new one.

Alternatively you can just add a rotation to your inventory variant.

Yep, because the item version of your block uses metadata:0. If you want it to be a different variant, you need to specify that. (e.g. getSubBlocks)

The ItemBlock still uses a metadata value somewhere. It's probably using 0.

That depends: is the default state the one used for the itemblock?

The entire Minecraft class is client side only: import net.minecraft.client.Minecraft;

Your crash occurs in com.minecolonies.colony.Colony which is not available on your github. Also what Jeffry said. Searched what class?

You'd want the only value for the singular variant in that case, yes.

Unrelated question: why does your class start with an 'I'?

It's just a loop that determines all the valid states and registers a renderer for them.

https://github.com/Draco18s/ReasonableRealism/blob/master/src/main/java/com/draco18s/ores/client/ClientProxy.java#L54-L56

Oh! Your block has several states. Are you holding one that does not correspond to the default state?

That should work, provided that the block has an item associated with it.

Did you register a renderer for your itemblock?

You need an inventory variant. You'd know this if you read the log.

IIRC, it gets truncated binarily to 4 bits. That is, 16 and 0 would be identical.