Dripping a wax blob with Down and watching the percentage meter and the candle fall made the cost of building feel real, and the dotted outline showing where the blob will land is a clear touch. The opening Market Row bubble only explains walking and jumping, so I found the drip by accident and only then saw the E prompt on the blob. Add a second bubble at the first step that says Down drips wax to build a step, and the core idea lands in the first ten seconds.