Guild Wars 2

In the Uncategorized Fractal the harpies are often invincible.
Try hitting them with any ranged weapons and you will see it say invulnerable.

This is obviously a bug because they should be damageable. They aren’t being instantiated correctly most likely.

Foes become invulnerable when the game thinks they can’t hit back. I’ve seen harpies start off vulnerable and become invulnerable as I moved out of their range. It’s annoying and it would be great if that stopped happening. All the same, it’s easier to work-around by engaging them in melee.