If you ask players who is the best warrior race, most will tell you Ogre.
Ogres have many perks, but their regeneration is what makes them fantastic vs other warriors.
But there is no way for a warrior to reliably block that.
So why not introduce a new lore that grants that ability?
The candidates are:
Poison - but poison can be cured easily.
Wounding - great, if it works like poison.
Plague - Even greater than poison, due to huge regen cut. And sound powerful enough as a Warrior lore should be.
I thought of "Belly cut" where you stick your weapon on your opponent belly and make the intestine fecal mater spill into the body, creating an infection. It should not be a disembowelment due to chest armor.
It should do some damage. Perhaps 50, internal.
As weapon I though of using Sword for the weapon lore.
We could also make double sheath a generic lore, needing no particular weapon mastery.
Also, I think Powergrip is a bad lore. Just think how many people use it.
WARRIOR LORE
A group of skills developed by various warriors and over time passed onto the guild in order for others of this profession to benefit. Only a single choice dependent on your weapon mastery maybe be made.
mastery allows ANY shield expertise, shield bash dagger, sword feign, doublesheath spear backcutter staff backcutter, powergrip flail mantis maul mace focused bash exotic weapon seize whip weapon lock axe, polearm powergrip
You may get further help on each of these skills.