A viable resolve tree - detailed changes

Recovery - changed to Stone Skin - decreases damage recieved from auto attacks by 0.6/1.2/1.8/2.4/3% Unyelding - bonus increased to 2/4/6/8/10% bonus armor and magic resist

so in this branch you have a choice, what kind of tankiness would you need the most. enemies have a lot of auto attack champions? take stone skin. Unyelding would be great against bruiser/assassin/mage comps, better for tanks as well as they stack resistances

Explorer - changed to Greasy Ground (whatever) - decreases movement speed of enemies that hit you by 8% for 1 second Tough Skin - reduces damage taken from champion and monster basic attacks by (0.5 x level). reduction is calculated after armor reduction

need to provide more utility for your team, or just want some end game tankiness?

Runic Armor - unchanged Veteran's Scars - changed to 1.2/2.4/3.6/4.8/6% bonus health

obvious change that should have been made long time ago. Runic Armor is decent and doesn't need a change, good mastery for tanks with high regen and sustain, also nice synergy with heals/shields, Veteran's Scars for hp stackers which would provide extra tankiness. not too overwhelming, extra 60 hp per 1000 hp from items

Insight (this should be tier 4 cunning mastery) - changed to Impenetrable - reduces effects of penetration on you by 50% Perseverance - you recover 1% of your missing hp over a second while being hit. effect lasts 2 seconds

here you can actually make a valuable choice again - enemy team is full ad/ap? they will get punished for that with Impenetrable. or you just want to further increase your perseverance the lower you are?

Swiftness - unchanged Legendary Guardian - you gain 1.5/3/4.5/6/7.5% bonus armor and magic resist for every ally near you (600 range)

by changing legendary guardian you can have a choice what do you actually want to do in a teamfight. if you want to be an annoying disruptor that sits on crucial enemies, you will take Swiftness (by the way, it would scale nicely with Greasy Ground). if you want to be a peeling machine, Legendary Guardian would be perfect. once again, first one is probably better for bruisers, second one for tanks

Grasp of the Undying - unchanged Bond of Stone - unchanged Strength of the Ages - you gain an additional 1% damage reduction on being hit (2% for spells and abilities), up to maximum 10% damage reduction. stacks last for 4 seconds

so, Grasp is a good choice for bruisers that want to have some additional damage and sustain and i think this mastery is well balanced after its nerfs, Bond is an obvious choice for tanky supports that want to protect their ad/ap carry and numbers are well balanced as well. Sota should be changed for multiple reasons. tanks are as squishy as they are now, because they are lacking of multiplicative reductions. current Sota was abused by many junglers who were supposed to be squishy (nida), but extra 300hp broke them and allowed to go full damage with items like rylais or roa. this is why stacking damage reduction is way more healthy, as it's still useless on damage dealers (as they will explode too fast to even stack up reduction) and actually useful on tanky champions. besides, my version is pretty much an equivalent of Fervor, so it can't be too strong, right?

in conclusion, these masteries could be looking op at the first glance, but they are not. first of all, it's just how atrocious current resolve tree is. secondly, if you think about it, every branch in ferocity tree has around 5% or more multiplicative damage scaling. why couldn't resolve tree have it? it would have bunch of actually meaningful defence and support masteries, that could have as much impact as ferocity and cunning tree currently have