PSA in regards to onigar and them hitting shields. IF suggested the following Trick as an option on Discord:
Strong Shield: Essentially, you use your willpower to paint on a layer of ordstirr which explodes out in a minor burst of concussive force when impacted, stopping any damage from getting through and sending the attacker flying.
This might not fully stop onigar, but it'd help, I'm sure. It is available to anyone with the actual Shield skill. Ragnarr is definitely taking it since he has that skill.