Which is bulkier: 252 HP / 128 Def / 128 SpD or 4 HP / 252 Def / 252 SpD?

To give a pokémon as much bulk as possible to reduce the most damage on both sides, which EV spread is better for them? Is it better to give a pokémon 252 EVs to HP and then 124 EVs to both physical and special defense each, or is it better to give a pokémon 252 EVs to both physical and special defense each and then give them 4 EVs to HP?

Pleaselog inorregisterto add a comment.

The answer depends on the Pokemon’s base stats (specifically, the ratio between its HP stat and the defensive stat in question). In the vast majority of cases, 252/128 is superior to 4/252. However, this is not to say that you should use either of those spreads in practice.

You can easily prove optimal EV spreads using adamage calculator. Below are calcs showing that for a Pokemon whose base HP is equal to its defensive base stat, 252/128 is better…

…and when HP is much higher than the defensive stat in question, there is an opposite result:

252 Atk Salamence Dragon Claw vs. 252 HP / 128 Def Blissey: 360-424 (50.4 - 59.3%) – guaranteed 2HKO252 Atk Salamence Dragon Claw vs. 4 HP / 252 Def Blissey: 267-315 (40.9 - 48.3%) – guaranteed 3HKO

However, if your takeaway from this is “always use 252 Def / 252 SpD on Blissey”, then you are thinking about EVs the wrong way. Balancing EVs equally in both defensive stats is a lazy strategy that ignores realities about how you will use the Pokemon in the context of a team. In singles, Blissey almost always uses 252 HP / 252 Def or 252 HP / 252 SpD because a team of six Pokemon invites you to specialise your Pokemon. Your Pokemon don’t need to be jacks of all trades (andmasters of none) when you have five other team slots.