Ok, the question is simple... If I reveal Threat from the north and then I attach a Flame Kissed on a strenght 3 character, does that character die for the attachment, or he must be discarded from play because of the plot text?

Technically, it does both.

The First Player decides the order of the conflicting effects. Whichever one s/he says "goes first" is where the character ends up.

For further clarification, see the FAQ , page 6 under "Simultaneous but Conflicting Entry into the Moribund State."

ok, thank you very much!