Basic Necron Warriors have always been innumerable and disposable.Their number is legion, their name is death. Lorewise gauss weapons shred their armor i guess, but it's also been inconsistent as they are not always high AP on the table.

Usually if Necron Warriors are portrayed as unstoppable killing machines it's because they were in their pre-5th edition lore where they were on par with space marines, and limited in number because it's always on a Tomb World that is just starting to wake up.

[–] Skua@kbin.earth 1 points 1 day ago

Ahh, that thing about the editions tracks with when I was playing on the tabletop. There were a couple of necron armies in the group I played with and they were always right stubborn bastards to put down. They didn't hit that hard, but you sure as hell had to hit them hard if you wanted to make any headway