Hat Blocks
When Green Flag Clicked
onflag { # code }
When Key Pressed
onkey "enter" { # code }
When This Sprite Clicked
onclick { # code }
When Backdrop Switches To
onbackdrop "backdrop" { # code }
When Loudness >
onloudness > 100 { # code }
When Timer >
ontimer > 100 { # code }
When I Start As A Clone
onclone { # code }
When I Receive Message
on "message name" { # code }
Source