[Fern]

It's not possible to target Frost Tyrant at all at times. Here's a screenshot:



The details I can currently provide after getting into repeat encounters with them:
1. This occurs when they freeze you.
2. No targetting is possible with any form of attacking or skills.
3. The screenshot has me trying to target the tyrant with a Moonlight Mercy.

In my experience, there hasn't been a single time when I can't target them while NOT frozen.

However this happens on-then-off after they freeze me.

The character in the screenshot is at red HP since it was not possible to target the mob, it was also not possible to get out of Life Eater.

[Neus]

A slippery enemy that cannot be targetted by skills that target enemies, if the user of that skill is Frozen. (Includes basic attacks.)

[Fern]

Oh whoops, my bad, I missed that completely.