[FINALLY!! he decides one's come just close enough and bolts up after one that's practically on the shore. Just too close for the lizard to react effectively.
It tries to dive beneath the surface, but water is too shallow and the blade of Scowl's knife is right behind it. When he straightens there's a lizard stuck to the end of his blade :>]
That's how you do it. A solid motion that you don't let go of.