This is Part II of a multipart series exploring the fundamental nature of hail growth through a toy model developed in Part I. The toy model uniquely parameterizes all hail growth processes by single-valued parameters with great computational efficiency. The parameters are uncoupled so that environment, storm, and hail embryo characteristics, and their impact on hail growth, can be studied independently—a task 3D trajectory models cannot perform because of their highly coupled nature. Three Monte Carlo simulations were run to compare hail growth from small versus large hail embryos and coupled versus uncoupled model parameters. Hail with maximum dimension D ≤ 25.71 cm grew in the physically coupled small-embryo simulation, D ≤ 33.59-cm hail grew in the physically coupled large-embryo simulation, and D ≤ 44.97-cm hail grew in the uncoupled large-embryo simulation. The largest hailstones from the three Monte Carlo simulations took similar trajectories, accumulating a large proportion of their mass both while suspended and during their fall. The analysis of model parameters corroborates current hail growth theory, indicating three necessary ingredients for large hail: 1) a favorable embryo size and location, 2) a long residence time in a water-rich updraft, and 3) a balance between updraft vertical velocity and hailstone fall speed. The sensitivity of hail size to these parameters is analyzed: A hailstone’s potential size is limited by its updraft-pass duration and the available amount of supercooled liquid water, but hail size is most sensitive to the balance between its fall speed and its encountered updraft vertical velocity.