The Dink Network

If it's a custom sequence, the simplest way would probably be to add a blank image as the last frame of the sequence.

EDIT: Not applicable if you don't want it to always happen, though...

sp_brain(&current_sprite,7);
sp_sequence(&current_sprite,###);
sp_frame(&current_sprite,1);

in void die() might also work. I've personally never got the point of creating a copy of the current sprite, just doing stuff in the die procedure is so much simpler.