Assyria Conquers Israel?

[Sean]

If X is 0, is it possible for the opponent to use the instead part of the special ability?
http://www.redemptionreg.com/REG/assyriaconquersisrael.htm

[crustpope]

Yes, they just discard 0 cards to stop you from d/c an ot fort.  Now if x=1 or more and they cannot discard a card (due to JR, HSR or they are decked out) then they have to discard the fort because they dont have the other option to go for.

[YourMathTeacher]

I'm pretty sure this card was intended to be used by an Assyrian defense only.

[Bryon]

Crustpope is correct.  If X=0, you can discard 0.  However, if X=1 and you don't have 1, then you lose the fort.  Likewise if X=1 and the discard part of ACI is prevented by Jerusalem Tower.  You lose the fort.

This is similar to Jephthah.  You must discard one to use the ability.  If you don't have one, you can't use it.