Heh I have all the natures written down on paper somewhere. As for IVs its more complicated. Lets see if I can explain. IV stands for Individual values. There are set numbers that range from 0-31. These numbers help determine how fast that certain stat will grow. From my experience 30 and 31 will always give you the max benifet. Take Jolteon for example,his highest speed can reach 397. But having a speed nature alone wont get you there. Thats where the IVs come in. lol long I know...But I'm not done yet....then again I dun know if I'm right....