Ferocity Needs a Meaningful Choice with % AR or MR Pen, Like Flat Pen, AD/AP, and Bonus AR/MR Have
The two tier 5 ferocity choices, Battering Blows and Piercing Thoughts, stick out like a sore thumb on the mastery tree.
Every other mastery choice is between vastly different effects, which forces you to make a meaningful decision around your champion and playstyle, and every other AD/AP, phys/magic, or AR/MR mastery affects them both in roughly equal regards, to make you decide between it and something else awesome in a different way, rather than a simple min/max optimization around your champion's damage type.
Look at tier 5 cunning masteries - the choice between Flat AR and MR pen, or 5% CDR that goes over the cap. This is a VERY real choice; sure certain champs synergize stronger with one than the other, but both masteries affect very different things, aren't specific to AP or AD, and have appeal to every champion, even if one is superior.
Look at tier 3 ferocity masteries; they're between lifesteal and spellvamp or per level AD and AP: between sustain or damage. Sure, some champs get extra benefit from the AP and AD due to good hybrid scalings, or reduced benefit from the vamp due to doing mostly AoE damage, but the choice is between two radically different things, everyone benefits from either one, and one is never strictly better than the other for any champion. There's no discrimination between AD or AP, nor auto based or spell based.
All the mastery choices are like this except the tier 5 ferocity choices of Battering Blows and Piercing Thoughts. 7% physical or 7% magic pen is the least meaningful choice any champion can make; all but a few champions do noticeably more damage of one type than the other, and therefore want the corresponding penetration, while there's no noticeable difference in effect between the two for the few champions that manage close to 50/50 split.
As much as I'd like the two masteries to be combined and another option added to take the space that'd open, I know masteries are too late into the development cycle to have any likelihood of major functionality changes until next preseason, but number changes alone could make them unique beyond being uniquely uninteresting. Unsurprisingly, understanding number changes requires understanding numbers, so let's start with some math.
Every 5 point mastery right now either offers linear returns, where each point gives as much benefit as the last, or offers increasing returns, where each point offers more benefit than the last. The 1.4% pen per point that Battering Blows and Piercing Thoughts offer actually has increasing returns, as each % of pen is a greater increase in damage than the last; As the most extreme example, reducing a 200 armor (66% DR) target to 100 armor (50% DR) with 50% pen is a 50% increase in damage, while reducing a 200 (66% DR) armor target to 0 armor (0% DR) with 100% pen is a 200% increase in damage. Yes, the increase in returns for five 1.4% steps is much smaller than in two 50% steps, but the math works out the same. Anyway, because all 5 point masteries all offer either linear or increasing returns, the choice is really between a 5/0 or 0/5 split; when one option is worth a point over the other, it's always at least as worthwhile to give it the next points.
Because 5 point masteries all of have linear or increasing returns, the point distribution in them is currently entirely about WHAT you want. However, the extreme similarity between Battering Blows and Piercing Thoughts offers a unique possibility for meaningful decisions around HOW MUCH you want each one, through strong diminishing returns. If both offered 2.5/4.5/6/7/7.5 % pen then the choice for point distribution would be over the degree of physical vs magic damage dealt, not the greater absolute.
Imagine you're playing Draven. Your kit is entirely physical damage, so a 5/0 split seems to make intuitive sense. But you love to build both Statikk Shiv AND Rapid Firecanon for the MASSIVE long-range crits. Those two items end up doing quite a bit of magic damage, so with a 2.5/4.5/6/7/7.5 % system you'd realize that getting 2.5% magic pen at the cost of .5% armor pen with a 4/1 split is quite worthwhile. At the same time, another Draven who likes to go for Phantom Dancer and Essence Reaver instead of SS and RF has no desire for magic pen whatsoever, so would still go 5/0. In this way, Battering Blows and Piercing Thoughts could offer unique and meaningful choices for every player on nearly every champion, based around their play style, preference, and desired itemization. It'd also make them less non-optimal for hybrid champions, even though 6% pen for one part of your damage and 4.5% for the other part is still strictly worse than 7.5% for all your damage.
2.5/4.5/6/7/7.5 % makes a good example, but is rather extreme towards the edges. While I doubt 4/1 (and 1/4) splits would be too strong thanks to penetration compounding (increasing returns) and synergy with stacking other sources of pen, player satisfaction would suffer from the last point in a 5/0 split looking so worthless, and ultimately player satisfaction is much more important than slight number optimization. Instead of the example's 2.5/2/1.5/1/0.5 % per point, a similar split that's less regressive while following the same general formula and bounds is 2/1.75/1.5/1.25/1 % per point, for a net of 2/3.75/5.25/6.5/7.5 % pen.
Regardless of Riot's standard developmental process or exact details, there's no good reason for why the choice between Battering Blows and Piercing Thoughts should be so awkwardly trivial, while the choice in every single other mastery split blows it away in comparison.
(I'll be writing more about the mastery and items changes in preseason 6 soon. For an in depth analysis of every non-item, champion, or mastery change, of which there's suprisingly many, read my post The State of Marksmen, part 3 (What, Why, and How the Preseason Changes the Game.) For why marksmen needed a rework in the first place, check my post** The State of Marksmen and the Meta Explained, part 1 (Why they Need the Rework.)** For what the rework does and doesn't accomplish in dealing with why they needed the rework, check my post The State of Marksmen and the Rework Explained, part 2 (Why this Rework isn't it, Yet.)
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