Changelings formless horror.

[Arkiham]

This abilities states that you can use a weapon of your opponents attacking using its profile, is this restricted to the statline, for instance 2+3+-1 rend 3 damage or, does it include any inate abilities of the weaponry,  for this example slayer of kings. 

[Double Misfire]

RAW it says "attack with that weapon, using it's profile" and not "attack with that weapon using it's profile and any abilities it might have on the target unit's warscroll", so I'd opt for saying you just got the weapon's statline and not any special rules it has.

Interesting case though, and worth hitting the faq guys up about.

[Changer]

I would say no, as these are abilities and not the weapons profile.  In addition to that, the ability for the Slayer of Kings states "If Archaon directs all if his attacks...", so the Changeling wouldn't be able to benefit from that ability.

[Terry Pike]

We discussed this for the Masters a few weeks back. No where in the rules does it actually say what a weapon profile is and what it is made up of.

Is the profile just the stat-line? Is the profile the entire weapon including any related rules? Is the profile just the text attached to the weapon?

There is no actual answer, as a weapons profile is unclear on what it actually is or includes. So far at every event I've seen the Changeling at he has been able to Slayer of Kings off Archaon etc.

[Changer]

That's the problem though; even if we do concede that the text under 'Abilities' counts towards the weapons profile, all of Archaon's abilities (including Slayer of Kings) states "If Archaon" etc...  As the Changeling isn't 'becoming' Archaon himself, these abilities would surely never trigger?

[Terry Pike]

Other units have similar wording, I believe Retributors also mention themselves in the rule for the hammers. Its either very well thought out to stop the interaction with units such as the Changeling, or was just worded without regards to existing rules.

Hopefully it will be FAQ'd either way in the next update though.

[Arkiham]

Agreed, it's a very important distinction,  as it can change entire games.

As for instance if attacking the prime, do you add the additional attacks or start on the baseline, if the weapon it self is gaining attacks rather than the person does that count ? 

Do additional attacks count if for instance the model is gaining buffs from a bloodsecrator?

[redbeardboss]

yes you get it. The Slayer of kings is the weapon and the name of the ability attached to the weapon. If you used a starsoul mace you would auto hit d3 wounds just like they do.