This project showcases an easy way to detect if a sprite has been deleted. 1: In the first sprite, make a "for this sprite only" variable and set it to any non-zero value. 2: In the second sprite, repeatedly check if that variable's value isn't 0 using the ([variable] of [sprite]) block from the Sensing category. 3: If the variable's value is 0, the sprite has been deleted. Simple deletion detector in 2-3 scripts.