Sorry to disturb you again with some other questions about Dark Charm, but I have read all the rules, all the new FAQ and all the 26 pages about dark charm in this forum (by searching) and I still have 2 main questions for which I have not found a good answer still valid after the last change of the FAQ.
Let me explain:
As a general rule we have always said that during the attack made through Dark Charm the OL retains control of everything that the hero can use on a normal attack, except for hero's orders, spend fatigue, sacrifice health and exaust cards (skills or items), …and also the hero's defensive options.
For the rest the Overlord has control. So, we have always said, that passive skills and hero’s ability that give bonus damage to the hero, or that give him extra surges, or that grants him extra new abilities, if have no cost are usable by the OL… but after the last FAQ (The Final FAQ) it was introduced a new sentence that looks to change that concept. The sentence is the bolded one in the following text:
” Q: When the overlord is controlling a hero through Dark Charm, who decides how to spend the surges and power dice? Can the overlord move the character and attack, or just make a single attack without moving?
A: The overlord controls the hero for that attack, including the hero’s use of surges and power dice. The hero is considered an enemy figure with respect to the other heroes and a friendly figure with respect to the overlord’s figures while under the overlord’s control. The overlord may also play cards such as “Aim” with the attack. However, the overlord player cannot move the character or force the hero to spend fatigue to add to the attack. Also, the hero player, not the overlord, decides which if any of the hero’s skills are used (including skills whose benefits are usually applied automatically, such as Blessing). The hero no longer benefits from any other heroes with Command, but does receive a bonus from any of the overlord’s figures with Command. If the hero himself has Command, the hero player can choose whether or not to use it. ”

In the forum I haven’t found answers updated at the last FAQ, all the answers I have found looks refer to the OLD faq, the one without this sentence. Now I would like a clarification, updated at the last FAQ.

1- To determine who controls the hero ability of the dark charmed hero, are hero's abilities considered as skills? So, who does control the hero's ability of a dark charmed hero: The Overlord or the hero Player?
(here the list of heroes with useful ability for the OL for the attack of dark charm: Virah the Falconer, Andira Runehand, Battlemage Jaes, Landrec the Wise, Mad Carthos, Ronan of the Wild, Trenloe the Strong)
Now the question is born from an extreme situation happened the last week when the OL played dark charm on Battlemage Jaes:
- if the OL has control over Battlemage Jaes’s ability, ok no problem.
Else:
- Battlemage Jaes player decided to not use his hero’s ability during the OL’s attack.
He was equipped witch a rune as weapon, 2 runes in the “other” slots, and an armor that normally prevents the hero from equipping runes.
Thanks to his hero’s ability Battlemage Jaes can normally ignore this restriction.
Now the player turn-off his ability, he can’t no more equip runes together with this armor, so “someone” should decide which items should be taken-off, but the OL can’t equip the player during dark charm, so it’s up to the player decide which items does the hero take-off, and obviously he decided to place all the runes in the bag, so that the OL had control of a hero without a weapon and other runes.The OL sadly did a fist attack to the hero without doing any damage. And at the start of the next turn the player re-equip all the runes as free-action.
And so OL and Battlemage Jaes player have spent 30 minutes arguing about who should have control of the hero’s ability. And here we are, after a week still without a common opinion. Please help us.

2- After the Final FAQ, because of the bolded sentence, I read that ALL the skill cards are under control of the hero player, so it’s up to him, and not the OL, to decide which, if any, skill remain in use for the OL’s attack. So even passive skills with no costs of any kind are to be considered under hero player control.
Now the other “part-time” OL says that this is a non-sense because passive skills should be considered a permanent bonus to a stat (like damage, extra surges, range bonus, …) so they are under OL control, else if passive skills can be not used also power dices of each hero’s traits should be under control of the hero player because them too are a stat of the hero, but the FAQ clearly states that power dices are under OL control.
So in his opinion passive skills should be considered under OL control for the duration of Dark Charm.
And he says that the part of the FAQ that says “… If the hero himself has Command, the hero player can choose whether or not to use it…” refers to skill cards that are passive but grants a new ability, and in his opinion these type of skill cards are the only exception to the rule that passive skill cards are under OL control. (so Blessing is passive and grants a new ability to the hero (Command), so it’s up to the player decide if use it during the OL attack, same for Wild talent that confers Sorcery 1 to the hero).
So to resume his point of view: “passive skills with no costs are under the control of the OL, during Dark Charm, with the only exception for those passive skills that grants a new ability that the hero else would not have.”
My point of view: “ALL skills are under Player control”.
Now we don’t have reached an agreement till now. What do you think about it?.
2a- During Dark Charm, passive skill cards with no costs are under OL control?
(list of passive skills usable during the OL’S attack: Ambidextrous, Crack Shot, Inner Fire, Marksman, Master Archer, Mighty, Precision, Prodigy, Weapon Mastery, Wild Talent)
2b- During Dark Charm, passive skill cards with no costs that grants a new ability to the hero, like Command, are under HERO PLAYER control?
2c- Based on your answer to question number 1, passive hero’s ability works in the same way of passive skill cards?
3- If the dark charmed hero has a pet, does the hero consider the pet an enemy figure and the pet consider the hero an enemy, during dark charm? Or the pet change side with it’s owner (so they remain friendly each other, but both become enemies for all the other heroes)?
4- If a dark charmed hero doesn’t use 1 or more skills, during the OL attack, these skills have to be considered deactivated till the start of next turn of the hero, or the skills never got deactivated so they don’t need to be reactivated?

Thank you for your help.

I consider the latest change in the FAQ regarding Dark Charm and the use of skills quite unfortunate. I would stick to the ruling you mentioned that the OL may control and use anything that doesn´t take away anything from the hero - this seemed to be the spirit of all previous DC rulings. Actually, that would be one of the very few houserules I would implement if we continue with Descent at some point.

As for the hero abilities, these cannot be turned on and off at will of the controlling player. The hero abilities had been addressed partly when we prepared the FAQ proposal document, but FFG decided to change some earlier rulings and ignore most of our suggested detailed points.

As for your second question, there is no distinction between active and passive skills. As per the FAQ, not a single skill may be used by the OL when performing the DC attack. Again, this doesn´t mean that the skill is deactivated and has to be reactivated by the hero. It simply isn´t used during the attack.

As for the familiars, you´ll need to come up with a ruling yourself. On the spot, I can only think of Skye´s abilities to be important for that question. Maybe Pico and Alex would need addressing, too (but Alex was granted by a skill card, wasn´t it, so at least this case would be clear).