What is the name of the soundtrack in My Hero Academia season 3, episode 14 beginning at 4:10?
just to make sure was this when the class were being told about special moves?
The next music after that point (beginning 4:25) is 'Kibasen' Hopefully this is the piece you were looking for.
It's Kibasen, the 13th track from disc 1 of My Hero Academia 2nd Original Soundtrack.