Just what exactly is a Polychord???
Polychords are created when two guitarists play two different chords simultaneously, producing a new chord.
Let's use a simple chordal triad as an example (Root, 3rd and 5th intervals).
Combining an Am triad (A-C-E) with a C triad (C-E-G) forms an Am7 chord (A-C-E-G).
There are multiple combinations that can be created.
Here's another,
a C triad and an F triad forms an FMaj9 chord (F-A-C-E-G).
Experiment the possibilities and see what you come up with.........