Hello,
if you call "Dead;" just after switching images you won't have any
effect because the sprite is destroyed immediately after.

If you want to show an animation you have to switch images, get the
pattern count and start animating the new image. When AnimPos reaches
PatternCount of the explosion image you actually call Dead.

Of course you have to disable collision detection when the sprite is
exploding so a good way is to set a boolean like "isDying" where if true
you won't check for collisions anymore, or something like that.

Hope this make sense