Please help me understand why something in my code is acting like this? (UNET)

It's not broken, it works. It just kills me as to why it works, and makes me question if I actually know what's going on in the rest of my project.

So for a while I had a bug in my game, where the BulletImpact prefab, spawned when a bullet collides with an object, was spawned twice for the host player. (and once for the client) Today I decided to get around to figuring it out. There didn't appear to be any logical errors in my code, so I just started commenting out a few lines here and there, adding Debug messages, etc.

This was the broken bit of code:

Code (CSharp):

1. Rpc_BulletImpactFX(); //simply runs BulletImpactFX() for the clients
2. BulletImpactFX(); //run BulletImpactFX() for the server, because RPC's are run on the clients, not the host ... right?

AFAIK from reading the docs, a function that starts with Rpc and also has [ClientRPC] in front of it, can only be run from the server/host, and the contents of that function is only run on the clients. That kinda happens, except apparently, from my testing, Rpc is also run on the server. (what..?) I came to this conclusion because comment'ing out the "BulletImpactFX();" caused it to *still* be spawned on the server, even though all that was being called now is an Rpc.

In the Rpc, there is only one line. Instantiate(). No Network.Spawn or something, just a locally run Instantiate(). Can someone please help me understand why this is happening?

 

ClientRpc run on the server, at least when the server is also a client.