What, Hex is not like races with immunity. It will never block ultimates or let you shoot through shadow hunter immunity. It only procs off of skills like bash, vamparic, or allows them to shoot through molecule bubble. There is a flat 50% chance of evading one such ability. I'm pretty sure you don't get a round where hex works 100% of the time. If it is how you describe, there is no message saying as such like there is for athena.