I want to do
The bullet is in collision with green ,yellow and blue
Green yellow,blue disappears
The bullet disappeared
Red is created
The problem is: after the collision, the bullet disappears, the green disappears,
but some red objects cannot be created
Maybe create the object before you delete the other one?
Epicsleeper is correct. You cannot create an object at a location of an object that doesn’t exist.
Events happen in order, from top of the event sheet down. So do conditions. So do actions. While there could be a myriad of other issues with your events, you absolutely must move the “Create object blah at green.X()/green.Y()” action above the “Delete Green” action.