The target that the winged skeleton was searching for was the enemy's new troop carriers. Other than transporting troops, the main purpose of these carriers was to transport large equipment as well. Combat vessels could be used to transport troops, but not large equipment as most of them could not be dismantled into smaller components, hence they could only be transported with large troop carriers.
Constructing such troop carriers was as difficult as constructing combat vessels. Besides, Cloudflow only had one shipyard on the Separation Sea. Even if they worked as quickly as they could, building one troop carrier would still take a month's time.
