Mark 3 expensive: Silicon28 + Silicon28 = Nickel56 (PLasma)
Mark 3 cheap: Oxygen16 + Oxygen16 = Sulfur32 (Plasma)
Mark 2 expensive: Neon20 + Helium4= Mg24 (Plasma)
Mark 1 expensive: Carbon12 + Helium4 = Oxygen16 (Plasma)
That are just a few fusion processes, they all produce energy inside suns. The big suns are able to produce everything with mass numbers lower than iron60. So metal fusions for metals with higher mass number (gold, tungsten) would need huge amounts of energy.
There is currently no Neon and Carbon has no fluid version... Not that i can't change that...
Maybe have to be Implemented the Tier 4 and 5 Fusion reactor with UV and Max Voltage to generating Elements above Iron or you think this Voltage isn't big enough too ?
My fusion recipes respect the logic with energy only from elements below iron. Also Tier 4-5 fusion? The current recipes would not be that many even for a single tier, so no need to add even more. Also i have some strange behavior with UV and MaxV energy networks i have to find the reason for first.