Today I was playing halo 3 on the xbox360 it’s a bit old but still a great game I was playing the 1st level on normal and I found a skull sitting on a rock so I picked it up. After that I quit the level and activated the skull and it made my gun invisible and got rid of my crosshair and I looked it up on the internet and found that it was a silver skull witch is ok.

I found it when you 1st come into contact with the covenant the should be a brute in yellowy gold armour on a high rock above water and about five grunts once you kill them carry on down the river till 2 phantoms come to drop of some more brutes and grunts the 1st ones close but the over is in the distance further down the lake wait for the phantom to go and then start killing the brute and grunts once there all dead go right towards the sea/water and there will be a rock with a skull on it drop down onto it and you got the 1st skull. Note: you have to be on normal or upwards not easy.

Here’s a picture if it helps: