The two vacuum bombs together had the power of a rank 2. Unfortunately that was the limit of his gunpowder.
He knew deep down he can't make anything stronger even with more gunpowder, he can't even make stronger gunpowder.
If he infused it with stronger mana then mana would surpass the gunpowder defeating the purpose.
Instead he would just have a rank 2 attack with a wider range. Which meant he had to work on nuclear energy.
Next on his list was a nuclear energy, for that that he had already collected all the necessary material he needed.
The only thing left is to create a nuclear reactor, the second layer had an abundance of uranium.
The nuclear reactor will produce plutonium as a by-product and then he'll use it to create implosion type bombs.
He could use uranium to make the the bombs but it seems like making enriched uranium would be inconvenient.
Plus he can use the nuclear reactor as a power plant to produce energy for their daily use.
