knows not the tiger. This should be 'knows not the open sea - 大海を知らず, which is read as /taikai/, as opposed to /taiga/ 'tiger'

Wha... Whatever meaning could that have!?

I've gotten my level up in practices, so I do believe that I can do my best even in events, yes I do!

Well then, I've got an old Japanese saying just♡for♡you♡

It means that the frog inside its tiny world doesn't know of the existence of strong things like tigers out in the big wide world, or something like that~♡ Originally, that a frog in a well doesn't know that the ocean exists; i.e. you can't know things that you don't/can't experience/see/feel etc.