Sly Cooper and the Thievius Raccoonus

Story related. Cannot be missed. You will need all seven keys and to use them on the calderon that is going around in circles. Jump on it to proceed on to battle Mz. Ruby.

Make sure you hit Ruby as soon as you get close to her.

She will have you play some Voodoo Simon says. Playing this game is the only way to damage this alligator. You have to time the buttons you have to press. If you press a button to early you will get hit and same if you press it too late. The closer the button is to Sly the better he will dodge the button. The buttons show up on screen coming at Sly. The sequence you have to follow is:

After that you get off the turtle voodoo Simon says is over and you get the chance to hurt Ruby. After you hurt her the next round of Simon says starts. This time it's a little faster.
 

After that you get another chance to hurt Ruby. This time it's alot faster. The last sequence of buttons are:
 

After that you get on the platform where she is and go for the last hit. When she is down for the count you will earn yourself a trophy.

Fast forward to 2:30 to the start of the fight. Credits to sevinup07 for this video.