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>held items right away
>ability to run right away
>no IVs
>level curve of any Pokemon game will put your mon in the mid/late 80s by the time you reach the E4, Champion will have a full team of level 100s
>EVs work as follows:
>you get 1 EV per level you grow
>you allot the point manually to any stat when you grow a level
>this boosts that base stat by 1 point (so you can increase your BST with EVs by 100 points total)
>when you obtain a new Pokemon, the next time it grows a level, you will get 1 point for that level grown to assign in addition to the remaining points it would have gotten had you had it from level 1 (e.g. catch a level 17 Pidgeotto, level it up to 18, get 18 EVs to allot)
>you can reset and re-assign EVs at any time by visiting a Name Rater-esque character in-game (since growing a level triggers EV allotting, bringing a level 100 Pokemon to this guy will allow you to assign its EVs)
This is great in a few ways. Number one, manually assigning EVs regardless of the Pokemon you battle is great. Number two, gives incentive to train your Pokemon to level 100. Number 3, Level 100 Pokemon are valuable in that they have maximum possible EVs to assign. This is a really simple concept present in most RPGs. Not sure why it's so convoluted and secret in Pokemon. That being said;
>visible BST / EVs (two numbers on the stat menu will be shown, in black, the base stat, and next to it in red will be that stat currently with EVs. E.g. Charizard having 109 spatk and 11 EVs invested in spatk will show as: 109 / 120) [standard battle stats, nature, etc. will also be shown as usual)
>visible move adjustment (e.g. Flamethrower [usually 95 power, or I guess 90 now] on Charizard will appear as having 135. And for example if Charizard had a Charcoal or a similar item equipped, Flamethrower would show as having 162 power). Moves' power unaffected by items or STAB will appear in black, but if a move's power is altered, it will appear as Red (a decrease in power will be blue)