To clarify:

E.g. I am using Strange Delusions to e.g. give a character the Agency faction to attach Dynamite to that character during the same phase.

Does the attachment stay attached and usable after the phase?

Strange Delusions:

Attach to a character or support card. Any Phase: Exhaust Strange Delusions to give attached card a faction affiliation of your choice until the end of the phase.

Dynamite:

Attach to an Agency character. Action: Discard Dynamite from play to wound all characters committed to the same story as attached character.

I've also been wondering: Does Strange Delusions replace the faction or does it add a faction to a card?

1) No, the dynamite must be attached to an Agency character. Each time the condition is not meet (the character is no more an agency character), you must discard the attachment (see faq about attached card).

2) It doesn't say it replaces the faction. You add another faction until the end of the phase.

1) Ah, you're right, it's answered in the FAQ. What a pity!

2) Thanks for the confirmation!

This card is'nt useless, as it seems if you only consider this point.

I used it in a way to give Hasturian trait to one of my neutral Assistant, just before playing Victoria's protege ... and then play gain my assistant.

It's usefull when you need to give the affiliation for card like Emerging deep one... Give the affiliation of Cthulhu to one of the Miska character owned by your opponent ... And he will appreciate it !

Shadow company may gains one more skill, Nebulous ooze might combo with a character from another faction.

PRODIGEE said:

Thanks for providing some examples!