Iron Heart vs Virtuosa.

Hello everybody. Please help me to clarify it:

Supose a vampire with MEL try to call a political action and use Virtuosa at MEL level. Can a vampire B with pot and pre, untaped with 5 blooduse Iron Heart to cancel the Virtuosa, even if the pre effect is not being used?

Virtuosa
pre +1 stealth.
mel +1 stealth and +2 bleed, or +2 bleed. You cannot play another action modifier to increase this bleed amount.
MEL Only usable when the action is announced. This action is unblockable.

Iron Heart
pot pre Cancel an action modifier that requires Presence as it is played. That card has no effect. No cost is paid.
POT PRE As above, but cancel an action modifier that requires Dominate

Thank you all.

No.

david_magri wrote:

Hello everybody. Please help me to clarify it:

Supose a vampire with MEL try to call a political action and use Virtuosa at MEL level. Can a vampire B with pot and pre, untaped with 5 blooduse Iron Heart to cancel the Virtuosa, even if the pre effect is not being used?

Virtuosa
pre +1 stealth.
mel +1 stealth and +2 bleed, or +2 bleed. You cannot play another action modifier to increase this bleed amount.
MEL Only usable when the action is announced. This action is unblockable.

Iron Heart
pot pre Cancel an action modifier that requires Presence as it is played. That card has no effect. No cost is paid.
POT PRE As above, but cancel an action modifier that requires Dominate

Thank you all.

No.

david_magri wrote:

Supose a vampire with MEL try to call a political action and use Virtuosa at MEL level. Can a vampire B with pot and pre, untaped with 5 blooduse Iron Heart to cancel the Virtuosa, even if the pre effect is not being used?

When a card is in your hand/ash-heap/library etc., you can treat it as requiring any of the disciplines it requires. e.g. you're using Spirit Summoning Chamber to look through your library for a card that requires Thaumaturgy. You can find a multi-discipline card that requires tha/vis.

When the card is being played, it requires whatever disciplines you're currently using for it.

Rulings wrote:

When played, a split Discipline card counts as requiring the Discipline being used (for effects that enhance or restrict cards that require certain Disciplines). In the hand (or library or ash heap), the card can be considered to require either Discipline (for effects that retrieve cards that require certain Disciplines). [LSJ 20020510]

Ok. Its clear now. Thank you all.