I am currently trying to use calculus to solve a problem that I have been trying to determine for some time. I will present what I have determined so far. The Problem: A hero in a popular video game (In this case LoL) regenerates 7.5% of his attack damage as mana every time he damages a target (So if his damage is 100, and he hits them, then he regenerates 7.5 mana). The question then, is how much total mana the hero regenerates during the course of a match. There are two things that first must be considered 1. The hero's damage is a function of his level 2. For the sake of simplicity, The hero's level is a function of time I decided to hold some things constant and to treat these two things as linear functions. 1. The damage function came out to be D(L) = 68 + 2L 2. I artificially decided to assume that the hero would level once every 2 minutes, so the level function is L(T) = .5T + 1 After this I am sort of at a loss. I have thought of graphing the D(L) function in regular X,Y fashion, and then graphing the Level function as the Z, but am not sure. I am not looking for an outright answer to this, I very much want to figure this out on my own, but I am quite confused. Also, if it matters I have taken up to Multivariable calculus, so I am pretty familiar with some methods used. Thank you.