AP shaco normally is not a damage focus champ. Yes he can deal lots of damage but AP shaco is more of an annoying, utility/team support champ more. Boxes are for controlling/denying area. Ult is for both damage and fear effect. He's not like Renekton or bursing champ like Leblanc or high AP scaling like A.Sol. If you play him as a utility/ controlling/ annoying little pest/ go back behind and annoying their ADC... You will do great.