Invisible players?

Okay so, not sure if there's been a thread already created over this topic already, but has anyone else come across like, literally invisible players? I've found 3 today.

When I find them, the "invisible attacking on mobs" then cease.

Are these bots? Are they literally going invisible now?

If you're in ARR areas, there are RMT-related bots that use hacks to teleport around and engage enemies from beneath the ground.

Oh so they're beneath the ground? I see. Yeah I don't think I've yet to see any outside ARR regions. Man, it's a first I've seen this, it's really becoming such an annoying issue.

Unfortunately, it's unlikely it's ever going to go away as they've been around since 2.0, and even if SE were to eliminate their primary source of gil (The gil drops from the Amdapor Keep trash), they'd just find something else to exploit instead.

I've already seen the gibberish-named exploring alternative methods of gil farming such as spamming the Hall of the Novice trials or farming shards from the initial DoH quests,

Is that what all those people running under the ground are? I saw a few people like that and they ran into the ground in a group. Thought it was some kind of glitch (didnt catch their names, I have names tags turned off)