Vitamins have been used in Mainstream Pokemon Games for years, helping players increase the Effort Values of a Pokemon's Stats. The higher the Effort Values, the more powerful a Pokemon will be in that Stat Category. This remains true in Pokemon Sword & Shield; however, players can now use far more Vitamins on a Pokemon than ever before. Now, players can use up to twenty-six of each Vitamin on a Pokemon to completely maximize a Pokemon's Effort Values!
Vitamins really only work on Lower-Leveled Pokemon, mainly because their Effort Values aren't already as high as they are going to be. Vitamins will be absolutely ineffective on Fully Leveled Pokemon, which are Pokemon that have reached Level 100 and usually have maxed out Effort Values. In total, there are six different Vitamins, one for each Base Stat Category for a Pokemon: HP Up (Raises Hit Point Stat), Protein (Raises Attack Stat), Iron (Raises Defense Stat), Calcium (Raises Special Attack Stat), Zinc (Raises Special Defense Stat), and Carbos (Raises Speed Stat). Vitamins can be found randomly in battle, but, most notably, they can be purchased from the Battle Points Shop in Hammerlocke and the Pokemon Center PokeMart in Wyndon.
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