Upgrade tactic card & exhausted soldier deck

[conman53095@yahoo.com]

If I have a +3 soldier card (Arquebuser) and want to upgrade it to a +5 soldier (Knight) using the Upgrade tactic card but the +5 soldier deck is exhausted/empty, what is supposed to happen?

- upgrade card cannot be used?
- upgraded card can be used, but must pay another gold to get a +7 soldier (War Machine)?
- upgrade card can be used by pretending more +5 soldier cards exist?

Thanks

 

[sbaracleto]

If I have a +3 soldier card (Arquebuser) and want to upgrade it to a +5 soldier (Knight) using the Upgrade tactic card but the +5 soldier deck is exhausted/empty, what is supposed to happen?

- upgrade card cannot be used?
- upgraded card can be used, but must pay another gold to get a +7 soldier (War Machine)?
- upgrade card can be used by pretending more +5 soldier cards exist?

Thanks

Upgrade card can not be used, because that Arquebuser can not be upgraded to a Knight (no knight cards left).