Cypher ~ The Unbound
The Islington Gate is the device that Dr. Edgar Islington built to siphon energy from other dimensions. With a few modifications, it could also be used to move between worlds, though further study may be required on that front.
The Islington gate requires a number of components before it can be built:
Steel Carbide Ring
Edgar's original design of the gate required a strong conductive hollow donut shape to both withstand and conduct the energies involved in the process. Steel carbide was the compound used, but any strong metal will do.
There is a strong metal known as adamantine in this world. This would be a suitable replacement.
1.21 Gigawatts of Power
The Gate requires an initial input of power to start the process of generating power/creating portals. Once on, it is self-sustaining. However, getting this much power is a tricky proposition in this world.
A lightning rod could work, just have to wait for a lightning storm.
Another potential solution is to acquire a steam power generator from one of the more technologically advanced nations, and perhaps improve it so that it produces enough power.
There is also a third solution. Get a roc to use its lightning power on a lightning rod. It's so crazy it just might work.
Probably the most difficult component to acquire. The Gate requires a ring of free flying neutrons to be circling the gate, contained by the steel carbide ring. This required some advanced technologies in Edgar's world to produce, that might not be possible to replicate in this new world. This will probably require some sort of magical solution.
The Space-time Warp crystals that are used to my airships fly could potentially be used to bend the neutron ring into shape, but it's a tenuous proposition at best.
The Islington Gate must be mounted on a solid foundation. Rock or a suitably sturdy stone floor would do. Dirt or a ship at sea would not. This is probably the easiest component to find.
Finding a base of operations is probably the first step on the way to home.
This is a device made of basic electrical components, circuit boards and blinking lights. These components are easy enough for Edgar to find or manufacture himself, it just requires some time and effort to assemble them into the final product.
Only Edgar knows how to construct the Quantum-Static Fluctuator.