Delay climbing pick (waterfall item)

[Dragonstrike]

Don't worry, there's a Fly replacement.  You have to beat the Championship a second time to get it, though.  

I do agree the timing of the Climbing Pick is a little silly, but there's also very few waterfalls in Tandor.  And once you've climbed them all, there's practically no reason to revisit those areas.  Either Waterfall's usage as a field move becomes redundant immediately, or the Climbing Pick becomes almost completely useless because you have no reason to use it at all by the time you get it.  Waterfall itself is at least still useful for physical Water types like Gyarados.