Algodoo

Setting timeToLive to zero is different from "killing". When one geometry is set as a killer, it can, through a collision, kill other geometries that are not immortal. But when a geometry sets the timeToLive of another geometry (such as through onCollide), it is not "killing' the geometry, but rather it is forcing the other geometry to kill itself (sort of like forcing another person to commit suicide). That's why the scripted block in your scene appears to be killing the other immortal block that it collides with. You can do the same thing by setting the other geometry's density to zero.

OK then... should i rename it "Black that forses imortal blocks to commite suicide" xD

Why not?

at least its usefull