Ok I gave it more thought, some sample chains below...
(A)
<start chain>
(i) tap character to declare the play of item and place item with character*
(ii) opponent may reveal on-guard per rules because the company played a resource that potentially taps the site
<nothing more is declared, chain begins to resolve>
(iii) item is (succesfully) played: tap the site
<end chain>
*item is not considered in play until it has resolved
(B)
<start chain>
(i) tap character to declare the play of a faction, this creates an influence attempt with an influence check
(ii) opponent may reveal on-guard per rules because the company played a resource that potentially taps the site / in response to the influence attempt if certain conditions are met
(iii) play A Friend or Three to modify the influence check
<nothing more is declared, chain begins to resolve>
(iv) A Friend or Three resolves
(v) make the influence check roll, adding any modifiers
- -if succesful, put the faction in your MP pile: tap the site
-if unsuccesful, discard the faction
<end chain>
(C)
In this one Heedless Revelry is on-guard and will be revealed per card text: "...may be revealed as an on-guard card on a company in response to the play of an item, ally, or faction. Tap all untapped non-Ringwraith, non-Wizard characters in the company."
<start chain>
(i) tap character to declare the play of item and place item with character
(ii) opponent may reveal on-guard per rules because the company played a resource that potentially taps the site (but declaration of playing does not meet requirements of Heedless)
<nothing more is declared, chain begins to resolve>
(iii) item is (succesfully) played: tap the site
(iv) Heedless is revealed per its card text: tap all untapped non-Ringwraith, non-Wizard characters in the company
<end chain>
Note that it would be possible to declare Marvels Told after (ii), before the chain begins to resolve, but not in response to Heedless at (iv).
Thoughts??