So...I think here's my plan:
[X] Plan Breaking Charges And Slaying Falcons
-[X] Stoke Virthing (+42 Orthstirr)
-[X] 14d6 Attack (all tricks)
-[X] 1d6 Defense
-[X] 22d6 Intercept (all tricks)
-[X] As soon as the falcon is trapped or, if it escape the trap, when it comes in range, make two 7d6 (8d6 w/Hugareida) Firebomb Strike Attacks (-4 Orthstirr each) to try and finish it off. If it dies or flees, we have one left, and the opportunity is there we'll throw it at the squire putting in an extra 3 Orthstirr (-3 Orthstirr...7 total on the attack).
-[X] Prepare two Inertia-Arresting-Throws (-6 Orthstirr each) one at 10d6 (12d6 w/Hugareida) and the other at 12d6 (14d6 w/Hugareida, 19d6 with our +5d6 Muna, which we spend here) to use under the following circumstances: If the falcon attacks, especially going for our fylgja before it leaves, try and snare it in the 12d6 one. When the Squire and Horse charge, toss the 19d6 one at the horse's knees, hopefully bringing the charge to a stop (ideally in catastrophic fashion). We do these before any relevant Halting Vortex uses but will still use Halting Vortex if they don't work.
-[X] In response to any Trick Attack directly targeting us use Halting Vortex (-4 Orthstirr)...if an attack somehow gets through that or we have IAT up and running attempt to Sidestep (-4 Orthstirr) if possible. If our fylgja is attacked and the IAT for the falcon doesn't work withdraw it and use Halting Vortex no matter what (-4 Orthstirr). If we can also shield Abjorn on top of us and our Fylgja (or the Fylgja has fled) and IAT is not currently active use Halting Vortex to defend him as well if it looks like his own defenses have failed (-4 Orthstirr).
-[X] Tactics – First, have our fylgja give Abjorn a new shield while we defend it, then have it leave the material world. While doing that, tell everyone about needing to pour on more orthstirr to get through the armor. If the falcon attacks or the Squire charges during this, use our planned IAT options. Other than that, wait for the opportunity to use those (the squire charging and the falcon attacking both seem near certain) and target the falcon. If we have to choose between the falcon and the squire with IAT due to timing, we prioritize the squire (using Sidestep against the falcon) as long as our fylgja is gone by then (we will not use IAT on the squire until the fylgja is gone) and hit the falcon with IAT whenever the squire is no longer under it. If the falcon gets trapped, try and get the others to also attack it at the same time as us before it gets away, assuming they can. If the horse gets trapped, suggest people surround them.
Does that look workable to everyone? It's a little reactive, but I think it's a solid way to remove one of the squire's advantages (mobility and charging) and hopefully take out the falcon.
EDIT: Just remembered our never used '+5d6 once per combat' Muna. I think halting the squire's charge is the time.