Aggro, threat generation, and pugilists...

[Bixby]

I've noticed that for some reason, when a mob is getting kited, i can no longer hit it literally no matter what. Is this lag? I usually run less than 150, sometimes 200ms for my average speedtest ping, not bad for being in hawaii on a mobile hot spot. But its super obnoxious that i cant continue to deal DPS on a mob just because theyre chasing some one else. And they cant stop or they'll get melted.

Basically.

With FFXIV, the server keeps track of positions of everything, and anytime there's a conflict between what you see on your screen and what what the server thinks is happening, the server wins. By the time you get the data that a mob is at position X, if it's moving, the server already has it at its next position. You'll never catch something you're chasing until it stops.

This is also why, even if you think you're behind or beside the mob when you're solo, you'll almost never get flank/rear bonuses on any of your skills. It may look like you ran around to the side, but the reality is that mobs turn to face you instantly & constantly; you just don't see it.

To hit a moving mob as a melee, you have to run a little bit ahead of them. That puts you where you need to be according to the server, which already has the mob a few steps ahead of where your client shows it. How far ahead depends on how much latency you have. For me, I generally need to be right in front of them, with my feet just outside their targeting ring, unless they're moving at a slower/faster than average speed.

[Sisqi]

This is also why, even if you think you're behind or beside the mob when you're solo, you'll almost never get flank/rear bonuses on any of your skills. It may look like you ran around to the side, but the reality is that mobs turn to face you instantly & constantly; you just don't see it.

Does this apply when the mob is AoE casting and I strafe to the side or run thru to the back? Or is the impression that the mob is "stuck" casting also an illusion?

[Niwashi]

Does this apply when the mob is AoE casting and I strafe to the side or run thru to the back? Or is the impression that the mob is "stuck" casting also an illusion?

The mob will remain facing the same direction until it finishes casting, so that can sometimes give you a chance to get in a flank or rear attack. You may, however, see it finish casting a moment after it actually does. This can lead to being caught in an attack that it looks like you avoided if you're cutting it too close.