How do you beat Rickies?

The danger is in the opening string, not the Rickie itself. Once all three hits have been thrown and missed, it has little left to threaten you with.

So don't trade blows while the sequence is live. Let it start, dodge each of the three hits in turn, and save your damage for the window after the last one. Count the hits so you don't swing early after the second and eat the third.

Your levels decide how forgiving this is. If your Aniimo are underleveled, enemies gain damage multipliers and resistances. A missed dodge costs more, and the finishing window gives you less damage per second spent in it.