In ghost shooter, when a ghost is destroyed, a the monster sprite is removed and a explosion sprite is created where it dies. What you want to do is when the ghost is destroyed, create a textbox where it dies. This is done in event 5 of the tutorial version of ghost shooter. You need to create a textbox and add the fade behavour to it. Then change the event.
The event currently looks like this:
Condition:
Monster -> health <= 0
Actions:
Monster -> Destroy
Monster -> Spawn "explosion" on lair "main" (image point 0)
Explosion -> Set angle to "random(360)" degrees
System -> Add "Monster.Movement.Speed" to Score
You want the event to look more like this:
Condition:
Monster -> health <= 0
Actions:
Monster -> Destroy
Monster -> Spawn "Diabetes Text" on lair "main" (image point 0)
Diabetes Text -> Set text to "Diabetes is a group of diseases in which there are high blood sugar levels."
System -> Add "Monster.Movement.Speed" to Score
You may also want to create a dictionary or array of text about diabetes and set the diabetes text to a random message from it