My, aren't you a flatterer~

[While Mettaton would likely agree that extra-flexible limbs were a boon--just look at these wiggly arms and masterfully-crafted legs!--he wasn't in any position to craft them. He'd at least put for this best effort in studying the art and putting it to practice, though. He's a go-getter!!]

Oh, really? I don't know what a changeling is, but from the way you are describing it, it's rather self-explanatory. Though...a boat? That seems rather impractical.