Stone knows next to nothing about building. He's basically there to be big, strong(-ish), and hold things that would otherwise require multiple people or be very awkward for a human-sized person to hold. It also helps to have someone who can stand in the water without being in over his head, and Stone's winged form can do that in most places.

He also attempts to perch on the pylon logs once they're sunk, even jump on them a little in an attempt to get them wedged further down. It's a kind of funny picture, a big ghostly dragon-like thing hopping up and down on a log sticking out of the water, wings tightly folded but spines and frills all flopping around his head and shoulders.

However, he may be a shapeshifting dragon person, but he is still old, and has lost most of his muscle mass and magical strength in the past year or two. He requires a lot of sitting to one side catching his breath and letting his tired, sometimes-trembling limbs rest. He spends those rest periods in groundling form, so he can chat. Or, more appropriately, grouse. "I hate being old," he grumbles more than once. "If this were two years ago, I could keep going for hours."