[Droxx]

Bumping this as I also found the mez immune message patch notes while researching something else.

Currently trying to mez something that is immune (giants for example), it will simply return a resist message.

The stun immune message exists but only on effects that have additional components, eg T-Staff:

[Sat Jan 04 00:48:49 2020] Your target is immune to the stun portion of this effect.
[Sat Jan 04 00:48:49 2020] an elder temple defender was hit by non-melee for 120 points of damage.
[Sat Jan 04 00:48:49 2020] An elder temple defender begins to spin from one hundred blows.

If you attempt to stun a mob immune to stun (giants, 55+ mobs, etc) with ONLY a stun, it will not return an immune message, even if the stun is not resisted. Confusing, as there is no indication that the mob is not stunned, other than watching it and seeing that it still hits/casts.