Step 1: Press Back and go in option, set a button to have both attack and jump on it, to make the move easier. Do not make it rapid fire!
Step 2: Pick the panther
Step 3: Use the move **forward-back-forward attack+jump**, repeat the move on the other direction or back up a bit, rinse and repeat.
Step 4: Win
This move was actually xRogue 5x solution to get the True Ending. Credits to him.