What is this tiny creature doing on top of a giant sword.

Because it manages to get up there, as the sword is being drawn back - and the older man somehow noticing (probably from the pleas) that Potato is now on top of it, looking back at them. ...with the exact same furrow-brow expression of confusion at the new entry into their family tantrum spat.

'This ain't the place for kids,' the man says with a deep, gravelly voice. 'Scoot on.'

Tidus can be heard snorting, at least on his feet. Could he be taking this time to attack? (But Potato said no fighting!!)

"Really? What kind of illusion are you?"

Shouldn't he be wanting to fight him to the death or something?!