Ys IX Monstrum Nox : 'Overdrive' + 'Showstopper' trophies
Just showing ya how to do the 'Boost' + 'Extra Skill' moves. Attack til ya fill the orange meter, press R1+L1 to 'Boost', press R1+L1 again to use 'Extra Skill'. Do both 100 times for the trophy.
https://store.playstation.com/#!/tid=...