The armour would probably be fine. The wearer, less so.
Armor's purpose is to protect the wearer. If you include Warding and Spellbreaking onto armor with the Master Rune of Steel, both of those are meant to the
wearer of the armor. The spellbreaking rune says that directly on the Rune List spreadsheet.
Though this like idea of the Master Rune of Steel being effectively not worth using is a problem, but there's an easy fix:
@soulcake what is the point of the Master Rune of Steel in Snorri's mind? What does it provide to the armor and the wearer of that armor.
Would Pure Gromril even break down though? And I am wondering what combo we would even go with for the armor. I mean even if we ask for some T5 reagent we dont really have any special Armor Master Runes apart from the two.
So apart from using Adamant as the reagent for the Master Rune of Gromril for the Pure Gromril armor I dont really have any ideas for it. The claws get the T5 Dragon Brain but that's a separate piece.
Yes? It's not magic resistant like Adamant is. It won't break down when it comes mundane stuff more than likely but because it isn't magic resistant a Nurglite could totally point at it and zap it to make it corrode. It just might take them more effort compared to a more normal material.
The Master Rune of Gromril in all of its instances so far has been to increase the physical toughness of whatever armor it is put on. It is a very straightforward rune. The Master Rune of Steel I would argue is less so, which is why it comes across as meh.
My point is, that while M.R. of Currents can be boosted by Dragon Brain, it's possible that for the upcoming fights, the basic M.R. of Smiting might be more effective. The boosted M.R. of Currents rune might is probably the most individually powerful rune we can make, and give a bigger flat bonus. But tactically, we want the KoS to be killing big things, greater demons and dragons, where the three runes i suggested might be more effective than the combo being proposed.
Perhaps but we do know that Combos are generally more powerful than non-Combos, similar Combos are required for set bonuses, and we can make the Master Rune of Currents better than normal. Plus one of the main things defending big gribblies is either sheer mass or armor, and the Master Rune of Currents is about not being blocked, being faster and being sharper. That sort of thing can get around the defenses of gribblies, allowing the KoS to leverage his strength against the softer squishy bits.
Master Rune of Smiting, Rune of Daemonslaying, Rune of Dragonslaying in my mind might equal the advantages of the hypothetical Master Rune of Currents (Dragon Brain), Rune of Cold, Rune of Cleaving, cold based Combo in the specific situation of fighting big gribblies if it made a sort of Monster Slayer Combo. Like you have a point that big monsters are a general issue and what we can expect the KoS to fight, and there's a possibility your thing might combo. I would be happy to test both of them and go with the one that combos.