The Enemy pays Resources to recruit 1 Unit.
Units are recruited in priority order, meaning if they can not be recruited then move to the next Unit in order:
1 Air Vessel > 2 Sea Vessel > 3 Warrior > 4 Serf
Note: Serfs can only be recruited 1 at a time, not 2.
New Units are placed in the Region of the Hero who performed the action, and will now be part of that Hero's army.
If a Unit cannot fit in that Region due to the 5 Unit Limit a Region has, then it is placed in the Capital City.
If the Hero is in the Courtyard, place new Units there.
This action will fail if the Enemy does not have the required Resources available to recruit any Unit OR if no Units are available in the supply.