So, this is my first post, and I'm still pretty new to warmachine, but I've got a match against a known Rahn player coming up (45pts) and I just grabbed some new models, namely Kaelyssa and a MHSF. This is the list I plan to bring - and the player I'm matched against loves the Rahn theme lists. We won't be playing themed tier lists, but he cleaves pretty close to them in his composition (and that's also all he pretty much has to my knowledge.)
MHSF full (8pts)
-MHSF Commander (2pts)
Dahlia and Skarath (9pts)
Lanyssa Ryssyl (2pts)
Mage Hunter Assassin (2pts)
So, the Hydra and Phoenix are pretty obvious, and the Griffon is in because of the insane syngery it would benefit from the Arcanist and Lanyssa - who is also included because of her synergy with the Griffon and the MHA. She's got a 10" spell that lets a model make a charge or slam attack the target hit at no focus or fury cost at +3" - that makes for two really fast, really hard hitting things with pathfinder (and stealth if it's on feat turn) for Rahn to worry about. Skarath is in because spray really wrecks Battle Mages and Halbardiers (I know this from personal experience) and I feel I can effectively shut down and destroy all of his arc nodes with the MHSF and Kaelyssa and Eyriss.
Anyway, offer advice. I feel like this will be a strange and synergistic enough list that Rahn will have trouble getting his caster kill on Turn 3.