Bulk and EVing Ceruledge

19 Jun, 2026

Most of the time, it's better to invest 32 HP stat points into a Pokemon than 16 DEF / 16 SPD. This is because the damage formula is inversely proportional to both HP and the relevant defense stat¹. For example, here's the damage formula for a physical attack, stated in terms of the thing we're trying to minimize (the percentage of our HP that we lose):

When we're EVing, we're deciding how to allocate a constant number of points between our HP and the relevant DEF stat. This is a classic optimization problem, and the upshot is that we should usually train our Pokemon such that their HP and the relevant DEF are as close as possible.² For 32 HP investment to be as impactful as 16 DEF investment in terms of surviving physical attacks, the defender's HP would have to be double its DEF. While most Pokemon have higher HP than DEF, it's usually not quite double; for example, a zero-investment Mew (a Pokemon with 100 in every base stat) has 175 HP and 120 DEF. Thus, for e.g. a bulky attacker it's typical to invest 32+ ATK / 32 HP / 2 DEF rather than 32+ ATK / 17 DEF / 17 SPD.

This blog post is about some special cases. A Vaporeon waiting to be trained, for example, has 205 HP, 80 DEF, and 115 SPD. Vaporeon is what I'll call "top-heavy": its HP is much larger than its defense stats, by a factor of about 2 or more. This should mean that we want to invest less into HP, and much more into our defense stats — to the point where 16 DEF / 16 SPD could be as impactful on a physical attack as 32 HP. For example:

32 Atk Sneasler Dire Claw vs. 32 HP / 0 Def Vaporeon: 103-123 (43.4 - 51.8%) -- 10.5% chance to 2HKO
32 Atk Sneasler Dire Claw vs. 0 HP / 16 Def Vaporeon: 85-102 (41.4 - 49.7%) -- guaranteed 3HKO

How should we think about this sort of thing?

Bulk

To make calculation easier, I'm going to make up some units that are easy to manipulate. Instead of thinking of the above formula as an algorithm for finding the percentage of HP an attack will deal, we'll consider the numerator and the denominator separately. That is, we can calculate the amount of "physical bulk" a Pokemon has (the denominator) and compare it to the amount of "physical bulk" an attack deals (the numerator):

For example, a no-investment Mew has 175 HP and 120 in every other stat. This means that its neutral single-target Earthquake deals $0.44\times 120\text{ATK}\times 100\text{BP}=5280\text{"stats squared"}$³. We'll call that amount a "Mewquake" (MQ). By contrast, Mew's physical bulk is

If a (no-investment) Mew's single-target Earthquake does $1MQ$ of physical bulk, and a Mew has $3.97\approx 4$ MQ of physical bulk, we'd expect a high-roll Mew's Earthquake to do a smidge more than a quarter to another no-investment Mew. And indeed, when we plug it in⁴,

0 Atk Mew Earthquake vs. 0 HP / 0 Def Mew: 39-46 (22.2 - 26.2%) -- 8.9% chance to 4HKO

I've started thinking in these units, because I can just memorize my Pokemon's bulks in MQ and calculate surprisingly fluidly. Recall that a Mewquake is defined as the amount of "bulk" eaten by a neutral-nature, no-investment Mew (120 ATK) attacking with non-STAB, normal-type-effectiveness Earthquake (100 BP). All the relevant variables can be scaled multiplicatively. For example, if I were defending with my own untrained Mew (3.97 MQ of physical and special bulk) and wanted to estimate what my opponent's 32+ SPA Mew's Psychic after one Calm Mind would do to it, I could reason as follows:

• A Mew's Earthquake does $1$ MQ (by definition).
• $(120+32)$ SPA is about $\frac{5}{4}$ of $120$ SPA, so multiply by $\frac{5}{4}$.
• Psychic has 90 BP to Earthquake's 100, so multiply by $\frac{90}{100}$.
• A beneficial nature adds another $10$. Since $0.9\times 1.1=0.99\approx 1$ I'm going to say this cancels out the change in BP.
• Mew's Earthquake doesn't have STAB, but its Psychic does. Multiply by $\frac{3}{2}$.
• The psychic type is not very effective against Mew. Multiply by $\frac{1}{2}$.
• Finally, this Mew has a Calm Mind boost. Multiply by another $\frac{3}{2}$.

Thus, on a highroll I'd expect this Psychic to do $1\times \frac{3}{2}\times \frac{3}{2}\times \frac{1}{2}=1.125$ MQ of special bulk. My defending Mew has 4 MQ of special bulk. Thus I'd expect this attack to likely 4HKO but never 3HKO. And indeed,

+1 32+ SpA Mew Psychic vs. 0 HP / 0 SpD Mew: 41-48 (23.4 - 27.4%) -- 73.4% chance to 4HKO

This is, of course, how I do mental math now; if I've memorized my Pokemon's bulks in MQ, the only relevant number I'm unlikely to know without studying are opponents' ATK stats. (The capacity for mental math, along with catchiness, is why the units are Mewquakes and not, like, Incineroar Darkest Lariats). But it's also handy for thinking about the types of decisions one can make while EVing.

Case study: Vaporeon

To go back to our Vaporeon example, we can actually get slightly (but unambiguously!) better bulk by training defenses rather than HP:

Of course, I'm unlikely to give Vaporeon that specific investment (even if, somehow, I needed the other 34 stat points in SPA and SPE). For one, we often train our Pokemon to live specific strong attacks, which might require HP on top of a full defense investment. Furthermore, especially in doubles you have to account for what your opponent will actually be throwing at you. I'm less likely SPD to increase the probability of some Dragon Pulse 4HKOing instead of 3HKOing when I could be improving my chances against the Dragon Claws my opponent is more likely to aim into my physically soft Pokemon. What the bulk calcs do show, however, is that you should never ever run 32 / 0 / 0 Vaporeon; because Vaporeon is top-heavy, you always get more bang for your buck distributing the stats among your defenses.

However, Max-modest Vaporeon is, if you can believe it, a bit of an edge case. This effect shrinks even more when you add more stat points into the pool and therefore shrink the ratio between HP and defenses (e.g. when you use natures). When you add a few more stat points into the pool you get into a middle space, where you can get a strictly-better option by taking a middle path:

When you give Vaporeon a defensive nature and more than 32 stat points to work with, this strictly-better demonstration disappears. But the principle remains: even in cases where you're trying to maximize the amount of health bar you have left against combinations of physical and special attacks, it's not always correct to chuck as much as you can into HP.

Case study: Ceruledge

In Regulation MA, Ceruledge is a bulky attacker with useful typing, a setup move in Bulk Up, damage-based recovery in Bitter Blade, and threat of priority. These factors help it function as a bulky attacker. At NAIC, Dawei Si used a Ceruledge team, winning not only my heart but top 8 overall.

The question, of course, is how to EV Ceruledge to be a bulky attacker. Assume my heart is set on 32 ATK and Adamant (and to make the numbers simpler let's say I want a cheeky 2 SPE). How should we allocate the remaining 32 stat points?

A 32 / 0 / 0 Ceruledge (i.e. 32 HP, 0 DEF, 0 SPD investment) has 3.45 MQ of physical bulk and 4.17 MQ of special bulk. A 0 / 16 / 16 Ceruledge fares strictly worse, with 3.29 MQ physical and 3.86 MQ special:

At first glance, our heuristic holds up: Ceruledge is bulkier on both sides when its investment goes into its HP rather than trying to divide and conquer. Indeed, if we're trying to optimize against getting gunned down before we can act, this is what we should do.

However, Ceruledge's signature move Bitter Blade heals it in an unusual way. If Bitter Blade healed a set percentage of HP, like Recover or Life Dew, this wouldn't affect our investment.⁵ But Bitter Blade heals a percentage of the damage dealt. In other words, with respect to our Ceruledge's defensive investment, each Bitter Blade heals a constant amount of damage. This means that, unlike Recover, Bitter Blade heals a lower percentage of our health if we have a higher HP investment. Should this bias us toward investment in DEF and SPD rather than HP?

Let's run some more calculations. Imagine that our Ceruledge has survived a hit, cracks back with Bitter Blade, and heals 50 HP. We can model this by adding 50 to Ceruledge's HP stat, bringing its in-battle stat to 200 with no investment, and 232 with full investment. Observe the change:

The gap has narrowed! On the physical side, Ceruledge takes hits exactly as well (assuming, again, that it's survived and retaliated). On the special side, we're still weaker, but the difference is smaller. If Ceruledge continues to gain virtual HP by attacking with Bitter Blade, it becomes better and better to split the investment, for the same reason that top-heavy Pokemon like Chansey and Vaporeon prefer to invest in their DEF and SPD.

How hard is it to get 50 HP back? Here are some common opponents that you can smack for about 50 HP in one Bitter Blade if you're Max-Adamant:

• 0 Def Floette-Mega (47 - 55)
• 16 Def Farigiraf (47 - 56)
• 16 Def Maushold (47 - 56)
• 32 Def Grimmsnarl (42 - 50)

That's an awfully frail selection, but remember, if we don't have first-turn survival problems we have an item slot. If we can heal for 40 HP on an attack, we can make up for it with either a Charcoal (which will heal for another 8) or Leftovers (which will heal for another 9, or more if we have more HP). It's hard to pick between these two items; Charcoal also deals more damage, but if I had to fill out a teamsheet now I like that Leftovers also heals when we Protect, on our Bulk Up turn, if they Protect, and so on. Either way, here are some opponents we can smack for about 40 HP, or about 50 with Charcoal:

• 32 Def Floette-Mega (36 - 43)
• 32+ Def Farigiraf (38 - 44)
• 0 Def Staraptor-Mega (42 - 50)
• 0 Def Charizard-Mega-Y in Sun (38 - 45)
• 32+ Def Metagross-Mega (45 - 54)
• 0 Def Raichu-Mega-Y in Rain (33 - 39)
• 32 Def Mega-Steelix (36 - 43)

That's a little more reasonable. I'm not going to enumerate every Froslass, Cha, or Kingambit you hit supereffectively, but they exist, too.

The only stat that matters in this calculation is your opponent's effective defense, and the turning point is about 120. Any game where you heal fully off a +0 supereffective hit is a game where you're glad to have invested in defenses rather than HP. The same is true of basically every game where you heal twice off Bitter Blade, or heal back from them hitting you on your Bulk Up turn.

Again, this doesn't replace EVing for specific moves, or more generally trying not to get gunned down before you can do anything. In fact, I don't think I've demonstrated that you should be thinking about the world in which you get a good Bitter Blade off, as opposed to the one where you're trying not to lose on turn 1. Thinking in Mewquakes is nice, but if you're EVing Ceruledge you gotta think in Garchomp-Earthquakes. The Ceruledge queen Dawei Si ran 27 HP / 20+ ATK / 18 DEF with Colbur. I'm not sure what that's for, and I suspect it's a combination of physical and special sequences. If it's based on surviving a specific physical attack, I'd probably weigh it against something like 9 HP / 20+ ATK / 32 DEF / 5 SPD, which has greater special bulk if you heal back enough HP. If it's based on surviving a specific special attack, I'd almost certainly prefer something closer to 21+ ATK / 23 DEF / 22 SPD. But if it's based on maximizing odds against arbitrary double-ups into Ceru's slot, then frankly I don't wanna mess with it. Chesnaught's fence or whatever.

Conclusion

Did you know that if your opponent leads Charizard-Y Heat Wave plus Chomp Quake, you can switch in a sufficiently bulky Ceru, live the EQ somehow, and if you can get your speed control off your next Bitter Blade is 12 MQ? On a more serious note, Ceru is so good against Char-Y. It's kind of a toxic romance. Thank you for setting my sun, darling, I have something for you, too. This isn't a conclusion, but I can't be bothered; frankly, I need to do something other than multiply three-digit numbers for a while, like sleep or play the game I've been yapping about.