He believes he's practiced enough when his shirt is wet enough to become a little heavy and choosing a place outside he'll let the water flop off of him with ease with the use of his power. It's only after does he head back inside with a small dampness to his body and he'll make his way over towards Joker who seems hard at work practicing with a good set of knives. He does remember that conversation a couple of weeks ago.

Tyki, being far too mischievous, waits for Joker to throw a knife before his body moves in between him and the target. He leans back and settles himself right there in the middle of it before just casually expecting him to keep practicing. He shouldn't be grinning but he is. "So it is true. You don't just manage in the background~"