just make it display a string above the rock like for instance:
NPC Code:
#s(rockhit)
to do this just have it so every time you hit the rock, it does this function:
NPC Code:
function bombHit () {
this.numplus=25*(1+strtofloat(#s(rockhit)));
setstring rockhit,#v(this.numplus);
}
then you can make it so when the string #s(rockhit)==100 that it moves the rock or whatever.
lol i just did that off the top of my head I doubt it'll work but oh well you get the idea.