Although each upgrade increases the Landing Craft's capacity by one, not every upgrade improves your battling ability as much because each Landing Craft can hold only one type of troop. For example, upgrading to level 19, which has the prime number size of 23, barely increases your battling ability other than training one more while upgrading to level 20, which has a size of 24, increases your battling ability by a huge amount.. "The Gunboat provides fire support and battlefield supplies to your troops. It can also relay movement orders with Flares. Upgrade your Headquarters to access new . All levels of the Landing Craft are listed and explained on this page. Check out Tips and Upgrade Costs for the Landing Craft in Boom Beach..