Attach to a unique ally belonging to any sphere of influence.

Attached character loses the ally card type and gains the hero card type

Attached hero loses the hero card type and gains the enemy card type

What on earth happens if both cards are attached to the same character?

As an aside, Fallen Into Evil is rather sloppily written, since the passive effect "Attached hero loses the hero card type and gains the enemy card type" applies only when the card is a hero and not an enemy, suggesting that the card constantly switches between the two card types at all times!

Attached ally gains the hero card type and then the enemy card type.

Don´t have the card in front of me but I suspect ´Fallen Into Evil´ uses the phrase ´attach to a hero´... once it is attached the character in question need not fulfill the requirement any longer. Compare to play restriction on ´Burning Brand´ stating that it must be attached to a lore hero; it has been FAQ´ed that it will remain even if the hero was to lose the lore icon (perhaps having gained it from ´Song of Wisdom´ attachment)

Perhaps I did not explain my confusion sufficiently.

Sword-thain creates a passive effect on the attached character which is always in effect, and is removing the ally card type and adding the hero card type.

Fallen into Evil creates a passive effect on the attached card (actually it says "hero" but we must assume it means "card") which is always in effect, and is removing the hero card type and adding the enemy card type.

Thus there are two competing passive effects and I'm not aware of any rule about which one "wins" this particular fight. I can't think of a precedent where we have two passive effects attempting to reach incompatible results.

for me, there are no competing passive effects.

Before you can attach "Fallen into Evil" you have to attach "Sword-thain" -> Your ally is now a hero.

Then you can attach "Fallen into Evil" -> Your hero is now an enemy.

The odd thing is that if Sword-thain gets discarded after the character had Fallen into Evil attached, then you either have:

a) a card that is simultaneously an ally and an enemy; or

b) a card that has Fallen into Evil attached, with no effect (since it says "attached hero" and the card it is attached to is now an ally) resulting in an ally being stuck in the staging area

Although, I'm not sure if there is an effect that would make you discard Sword-thain or not.

Although, I'm not sure if there is an effect that would make you discard Sword-thain or not.

Uruk-hai Tracker's shadow effect

The odd thing is that if Sword-thain gets discarded after the character had Fallen into Evil attached, then you either have:

a) a card that is simultaneously an ally and an enemy; or

b) a card that has Fallen into Evil attached, with no effect (since it says "attached hero" and the card it is attached to is now an ally) resulting in an ally being stuck in the staging area

Although, I'm not sure if there is an effect that would make you discard Sword-thain or not.

Nice catch .. i think we have situation b) .. because the without beeing attached to a hero the card has no effect.

Would you still control that ally? It was either engaged with you (or another player) while it was a hero/enemy, or it was in the staging area. Would it revert to your play area under your control if Sword-thain were discarded?

Oddly, you can still trigger actions on heroes which have Fallen into Evil, as per the Khazad Dum rulebook:

Ah, but does a hero with Fallen Into Evil actually count as an encounter card? One might argue that it does not, it's still a player card and thus you can only trigger it if you control it, which you don't.

Or one might argue that because it is an enemy card, it has to be an encounter card.

If it is true that a card can be both a player card and an enemy type, it opens up some interesting possibilities for custom cards: player enemy cards that have a beneficial Forced effect when they enter play, leave play, are damaged, etc.

If it's still a player card maybe it's still under a player's control, because Fallen Into Evil doesn't say you lose control of the card!

Oh, the shenanigans

Hum, doesn't we have a word on the encounter-player card already? The ally that got called.

I seems to remember it was an encounter card because of it's back, and it will go into the encounter discard pile if he died or is discarded because of that.

Old and foggy memories...