My Serving Arsenal:
Greek Method: One step to the right, one pump, underhand hit. I usually say "HIBACHI!" when I hit the ball

EFFECTIVENESS: 9 out of 10
"The Hawaiian Punch" - Toss the ball up in the air and smack the ball with a punch.
EFFECTIVENESS: 5 out of 10 (Still at work with it)
The Original Overhand Toss and hit - Duhhhhhhhhh
EFFECTIVENESS: 7 out of 10
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My serving accuracy is still very high.