Ok so. The Fire Kings suck. Arvata is the only decent one because every other fire king either has a ridiculously handcuffed effect that wont make an immediate impact. This is mostly due to the fact that you have to wait until the next standby phase. Now onslaught is also bad because it has far too many restrictions and is actually a genuinely well balanced card. Circle of the Fire Kings could be good as it can cycle stuff with Kitt, but that's really unnecessary and overall almost never going to be impactful enough to warrant the slot.
Now. The synergy is actually pretty good. Arvata destroying Kitt and giving the ability to negate handtraps is very cool and good. Rendezvous and Garunix are awesome for being able to establish tempo and make pushes for lethal. Wolfbark is very cool and good and never a bad card to see in your hand.
You can ABSOLUTELY play the Simorgh + Stormwinds combo because setting up:
Simorgh + Statue + Arvata + Rendezvous in grave, is very easy and very strong.
I just wanted to show off something different in my video
See the deck played here: https://youtu.be/twGE88AddR4