when it takes damage it goes into stealth and runs away to try and flank you.. you can prevent them from going into stealth by hitting them with fire

So its regular Stealth, like a Ranger using Phantom, not Reaper Stealth, correct?
How high is the mobility value on that move?

the stealth is a "true stealth" and wont be uncovered JUST by flanking. only true counter is fire or spamming battle scanners

Necroing it because I started playing again.
That true stealth is awful.
Scanning protocol is one use, battle scanner is two uses, incendiary grenades are two uses at best. This thing spams its stealth every single turn.
If it would be stealthy like the assassin, with high mobility but a resonable chance to find it by anything else but consumables it would be fine. But as it stands once spotted it just sidesteps into a bizarro realm of teleportation only to reappear and deal unavoidable damage. And then it starts it all over again.
This is a very cool, with many outstanding designs and ideas, but the chameleon is awful. It should be the ranger chryssalid, but every time I see one I just think: "Oh, its the cheating one, time to savescum." On the mechanical level, the chameleon is just infuriating and I am fairly certain that even the game itself does not properly handle its behaviour.

edit:spelling

It's invisibility, teleportation. JohnMcHobo described it deftly. I hate them. Please just delete them. Ghost grenades are also absurdly OP