minetest.register_on_placenode(function(pos, newnode, placer, oldnode, itemstack, pointed_thing) if newnode.name ~= "default:torch" and newnode.name ~= "default:torch_wall" or minetest.get_item_group(oldnode.name, "water") == 0 then return end minetest.remove_node(pos, newnode) minetest.set_node(pos, oldnode) minetest.add_item(pos, "default:torch") end)