Base stats are a value between 1 and 255, which influence a Pokemon's stats at certain levels. It's really just a number that's part of a formula. A Pokemon at level 50 will have +5 added to the base stat, except for HP. HP is +10 to the base stat. (At level 50.) Base stats disregard IV's, EV's and Natures. The formula for calculating stats is; Hit Points: ( (IV + 2 * BaseStat + (EV/4) ) * Level/100 ) + 10 + Level Attack, Defense, Speed, Sp. Attack, Sp. Defense: (((IV + 2 * BaseStat + (EV/4) ) * Level/100 ) + 5) * Nature Value If you used Rare Candies, you miss out on EV's. For the Sleep Clause, it means that you can not induce sleep on more than one of your opponent's Pokemon. This is to prevent battles from becoming a rush to put your opponent's Pokemon to sleep.