Alexander's Ever-Expanding Tome of Knowledge, pt 2

[Sandman]

SCOUT FERRY

Construction-2 has got two breathing items, the ring of water breathing and shambler skin armour. Using only three of these, it's possible to send an unlimited number of scouts, spies or assassins through underwater provinces to land on the other side.

Give one scout the shambler armour and two scouts water breathing rings. Have them travel underwater until they reach a land province. Once there, give all the breathing items to one scout, and have him travel back underwater, whilst the other scouts disperse. Repeat as needed. It's time consuming, but efficient.