How could this be extended to a negative bomb space like in Bombe (https://store.steampowered.com/app/2262930/Bombe/ https://store.steampowered.com/app/2262930/

How could this be extended to a negative bomb space like in Bombe (https://store.steampowered.com/app/2262930/Bombe/ https://store.steampowered.com/app/2262930/Bombe/)?