If you would like to stick to the more realistic 'nukes' that don't use elements that could be considered 'cheaty':
If you need long ambient heat (like melting the nuclear bunker save), I usually add BCLN(BIZR) too. BIZR turns into BIZS in the trajectory of the flying BCLN, and it preserves the heat of the bomb for a long time.
or i just figured out, make a circle of titanium, then delete all of the center, so it is around a 3-5 pixel thick ring, then put a small amount of polonium in it, then fill the rest with deut and set its life to 70000 and wait
THIS POST IS FROM 2017
edit : oh noes im too