Hepheastus is the most op character/entity in the series given that they can learn and then just rewrite themselves to accommodate any flaw. This would make em unbeatable in the end.

Unless, Far Zenith used the same resources on Sirius, as what is available here, on Earth, to create their Spectres. It could be impossible for Hephaestus to create Zenith tech advanced machines. And what also needs to be done is, destroy the Zenith matrix printer. Along with any resources that Far Zenith brought along with them. That isn't found on Earth.

I hope we get a massive Kraken-esque machine.

In my mind I could possibly see Hepth having been able to create a small army of its most powerful machines within the Printer Matrix compared to a Cauldron, would possibly seek to build a machine capable of producing new machines in rapid succession, though for gameplay purposes maybe limited machines of the same size as the Printer machine with Hepth being only capable of building a small scale version of the Printer Matrix,

With another possible could be that Hepth could move towards more nanotechnology based machines combined with the more mechanical design elements of GIAI’s machine, with the potential that a central component could be built to make any kind of machine to work given present situation, though possibly limited by by number of nanoparticles, with some aspects being unable to be replicated in the short term in combat, with weapons such as the cannon on a Thunderjaw being unquie, with environmental factors also limiting machine forms, a Thunderjaw being unable to fight in a small cave or fly in the sky

Bieri triggered the printer self destruct sequence to prevent Hephaestus from using it further so heph will only have access to the cauldron network. We don’t know what resources were used in the Zenith’s tech. It is all very vague. I think Heph would be forced to work together with Aloy and Co to stop Nemesis given the threat it posses.

Forgot that Bieri destroyed the printer matrix. Has been a while since I last played the game....lol.

I believe we might get a new variant, like instead of Apex Thunderjaw, we could get something like a Zenith Thunderjaw. We could also get more use of nanotech from Hephaestus with machines armor or components able to re-assemble after tearing them, imagine a thunderjaw that could re-attach its disk launchers.