Before I stat that out I have to explain some things.
Combat Bonus is a stat in the combat system. It and Wounds form the core of the system. In the combat system you roll four d50s and add your combat bonus to each d50.
If you have a combat bonus of +25 it looks like this:
You -> 1d50+25, 1d50+25, 1d50+25, 1d50+25.
Lets say your enemy has +30 combat bonus.
The Enemy -> 1d50+30, 1d50+30, 1d50+30, 1d50+30.
A combat round works by you and your enemy rolling your d50s + combat bonus and comparing results.
Example Round 1
You -> 30+25, 33+25, 12+25, 40+25. Your results for the round are a 55, 58, 37, 65.
The Enemy -> 4+30, 5+30, 10+30, 20+30. The enemy's results for the round are a 34, 35, 40, 50.
You then compare these results in a specific order. Your first result is compared to the first result of your enemy, so 55 is compared to 34 here. That's a Win.
Your 58 is compared to the Enemy's 35, another Win for you. Your 37 is compared to the Enemy's 40, a Loss. Then your 65 is compared to the enemy's 50, another Win.
Because you collected three Wins, you Win the entire round as a whole, and then inflict 1 Wound.
[Structural, Lonely] Master Rune of Valaya's Purifying Radiance: Structures inscribed with this Master Rune must depict an image/statue of Valaya, and sanctified by a High Priestess of Valaya (first part mandatory; second part tradition). Allied defenders under the effects of this Lonely Rune are Unbreakable, Tireless, and gain Regeneration. Cleanses allies afflicted by enemy magic, such as Nurgle's Rot, every 2 turns, as their bodies grow feverish from having malicious magic purged by runic power. Invaders, especially magical entities, spellcasters, and Chaos-aligned beings, suffer debuffs within the vicinity of the structure, their very essence seared and burned. In addition, their magics and empowerment effects will be negated every 2 turns, the magics within unmade and converted into heat and light that sears the afflicted enemies inside out.
This is a pretty complex Rune. I will break it down by creating an example bastion and fighting force making use of it.
First, I must state that combat bonus comes from a item or structure's quality tier and not from the runes alone. Tier 3 is +5, Tier 4 provides +10, Tier 5s provide +20 as a baseline, last I recall. This is modified by Sets, but I don't want to get into that right now, it'd distract from the current discussion.
Mingol a Valdok (Bastion of Valaya's Eye) is a Tier 4 structure, inscribed with Valaya's Purifying Radiance. As an absolute baseline it thus provides +10 to any defenders within it or the rune's area of effect. The defenders also have their own stats.
Defenders Combat Bonus: +10 (Base Dwarf Warrior Skill bonus) + 5 (Runed Equipment) +
10 (Mingol a Valdok) + 10 (Grudge against attacking Beastmen) = +35, Tireless, Unbreakable, Regeneration.
Defenders are Tireless. They are immune to penalties from fatigue and can fight forever.
Defenders are Unbreakable. They are immune to penalties from Fear or Terror, and cannot be made to flee because of Fear or Terror.
They regenerate 1 Wound every three rounds (e.g heal 1 Wound on Round 3, Round 6, Round 9 etc).
Every two rounds (e.g Round 2, Round 4, Round 6 etc), remove any penalties caused by magical debuffs inflicted onto the Defenders.
Enemies suffer a -10 penalty to their combat bonus while in the vicinity of the structure. Magical and Chaos-aligned entities suffer a -15 penalty.
Every two rounds Enemies with magical buffs active lose those buffs and take 1 Wound.
This is an extremely powerful rune that very much evens the playing field for the defenders. The nastiest special rule there is the canceling enemy buffs and forcing them to take damage.