Stamina leech is easy to understand. With x% stamina leech you have a chance of x%, to leech an amount of stamina equal to your damage, you did. Quite easy. But I have absolutely no clue, how exactly life & mana leech works. Let's take a look, what uoguide.com says: Let's assume, I have a weapon with 45% HLL and my hit did 50 Damage. (50 * 0.4) - 40 = -25 (WTF?) And what does 0 to X mean? A random percentage from 0 to X? After writing this, this minus in the formula rather looks like hyphen to me. Well, now that would make more sense. Honestly, who wrote this? This is pretty confusing. If that's really a hyphen, a simple comma would be better. I.e. if I use the numbers from above, the highest leech possible would be 50 * 0.4 * 0.45 = 9. So I would leech a random amount from 0-9 hit points. Would that be correct?