Why did my Gyarados gain 14 attack in one level then 3 the next?

Question

Sup guys tldr will be at the bottom!

I'm playing Pokemon platinum and I just started experimenting with EV training. I negated all the evs my lvl 40 gyarados had with berries and then brought up his attack with protein until it was no longer effective. I proceeded to murder machops until my brain melted and when he leveled up he gained somewhere around 14 attack...success! He leveled up again and went back to +3 attack on his next level up. Does this mean I have to train his EV's every level in order to repeat the same effect of gaining 14 attack?

TLDR
why did my EV trained gyarados gain 14 attack in one level and then only 3 the next??

Answer 1

The problem is that you don't understand how the game figures out your Pokemon's stats.

Each time your Pokemon gains a level, its stats are completely recalculated. EVs are one of the factors that go into calculating your Pokemon's stats. The "+14" is from the game showing you the difference between what your Pokemon's stat was before, and what it is now after the recalculation. The difference is big on this occasion, because Gyarados has all these EVs it didn't have before.

The next time it levelled up, Gyarados got +3. This is because there is no longer a big difference between Gyarados' EVs from its old stat total, and its EVs from its recalculated stat total. The EVs are already there.

As you continue to level up Gyarados, all the EVs you trained will continue to be included in the calculation. This will lead to higher stat gains in general, compared to if you hadn't EV trained Gyarados. However, you will never see +14 again (and you don't need to), because there will never again be such a large difference in Gyarados' EVs between level gains.

In other words, the work is already done. You have nothing to worry about and you've done nothing wrong. If you maxed out its Attack EVs, then your Gyarados will have its best possible Attack stat at whatever level it happens to be at.

Answer 2

On level up, the game will calculate how much of a stat point increase you would have at that level and adds it on. For example, if you have a level 50 Gyarados and you earn 200 EVs (50 stat points), you won't get +1 extra point per level up. Instead, you'll get around +25 on the first level up (because at lv50 you would have earned about half the points), then +1 for roughly every two levels after that.

So because you were at level 40 you got a stat increase for what your stat should be at that level with the evs you have all at once, but then as you level up its more gradual. So if you had a level 99 gyarados with 0 EVs in attack then trained it to max attack EVs and levelled it up, you would see a very large stat increase.

You don't have to train EVs for every level, because EVs don't change when you level up.

Hope you can understand it.

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