Piccolo's ears twitched at the sound of the water splashing behind him but he didn't bother to open his eyes and investigate. He kept meditating without a hitch.

A little later he heard the sound of rocks tumbling down and a softly whispered word (that to his hearing wasn't all that soft actually) of regret. A rock formation suddenly appearing in front of him might have been more perplexing if it wasn't for the misfired attempt. Again, Piccolo ignored it though.

But when a third attempt to spook him or get his attention or whatever this character was trying to do, the Namekian finally slit one eye open to catch him in the act. Only to see nothing. Well. That was vaguely surprising.

He closed his eye again and let the rogue finish his rock sculpting.

Just as Caster might have thought his work was done and could wait to see the result an interesting action took place. One of the rocks that Caster had so painstakingly placed decided to hover in the air. It was only for a second--and then it suddenly darted towards the invisible man, smacking him somewhere harmlessly if he wasn't paying attention.

The green-skinned man didn't move. Didn't open his eyes. But...was that a small smirk on his lips?