Why not add a way to make them unmeltable by setting their tmp2 to -1, for example? It can't be hard, as its easily done in LUA, so is it related to that rule that elements cant have different functions?
I think its possible, instead of having "HighTemperature" and "HighTemperatureTransition", these metals could have something like
if tpt.get_property("tmp2", i) == 0 then
if tpt.get_property("temp", i) >= (melting point) then
tpt.set_property("type","lava",i)
But I understand that part of "secret" properties not being that good to change how elements work.
jacob2:
Thats the last thing we need. IMO, the game needs to be made as fast as it can be, not slower.