Pyroak looks like it could become an excellent wincon on fatter teams and stall. Its typing allows it to switch in hard and set up for free on pokemon like Jumbao and Ferrothorn, and its natural physical bulk means it's hard to take down once it gets going.
I literally sat this thing in front of a dragapult and got free spdef boosts from shadow ball this mon is cracked This does not mean Pyroak is not without problems. It's slow and without giga drain it will have problems with opposing Water types. Pyroak carries rocks on this team as a means of role compression.
Arghonaut checks a lot of Pokemon, such as Weavile, Crucibelle, Scizor, Volcorona, Heatran, Cawn... and helps weaken opposing teams with Spikes. Equilibra helps checks fairies and psychics and helps wear down teams with Doom Desire. It also carries Rapid Spin, which allows Zapdos to run Volt Switch, which allows it to pivot better. Zapdos checks pokemon such as Corviknight and keeps Tornadus from cleaving through this team. Jumbao also helps against bulky waters as well as dragons, which helps facilitate Pyroak's sweep. Finally, Dragonite is an additional wincon that checks opposing Pyroak and Heal Bell is very useful for keeping the team healthy.