This is the kind of thing that makes games so magical. When players can find ways to succeed within the rules of the game that a Developer never intended to, you know it's gotta be good. That's exactly what Dark Souls 3 player, The Zexster did when an enemy player invaded his game. Instead of confronting them, Zexster disguised his character as an NPC and remained (mostly) still while the other player simply passed him by.
Zexster didn't even try to hide, instead plopping his character down in the middle of the environment, so there's no possible way that the enemy player could have missed him. As time goes along, Zexster gets a bit bolder to try and entice the enemy player by walking around (even directly beside the enemy player), taking some damage from an enemy and even lighting his scythe on fire.
But nope. Nothing. It's hard to tell if Zexster was just that good or if the enemy was just that dim. Either way, it makes for an entertaining video.