??? element would suck but antimatter could be good. Element:Antimatter(AMTR) Propperties: Special element. When touches anything but itself or walls it will create a huge explosion. Powder.
Lol, if Lolzy knows what it is and doesn't like it, I guess that's that then. XD
Pilojo: ??? is basically an element that gobbles up empty space and everything else like an explosion, but leaves nothing left behind when it fades away.
Maybe a similar element which climactically wipes the screen of all "organic" (not walls) material. Then one that does the same with inorganic materials. You could just use erasers, but it would look cooler if you did it this way and it would be fun to make shelters for stickmen from the virus.