This is probably the best TL;DR: The author created a nice way of specifying loot dropping behavior such that (begin quote): "Any monster has a chance of dropping almost any item, so you have that pleasant anticipation. At the time time, the probabilities are weighted so that each monster still has a unique “feel” to their drops, and you can seek out monsters that are more likely to drop what you want."
And the author achieved this with a concise but clear DSL in which you specify the probability of starting at a particular point in the equipment hierarchy, and then an object is chosen by traversing (probabilistically) the equipment hierarchy.
This is probably the best TL;DR: The author created a nice way of specifying loot dropping behavior such that (begin quote): "Any monster has a chance of dropping almost any item, so you have that pleasant anticipation. At the time time, the probabilities are weighted so that each monster still has a unique “feel” to their drops, and you can seek out monsters that are more likely to drop what you want."
And the author achieved this with a concise but clear DSL in which you specify the probability of starting at a particular point in the equipment hierarchy, and then an object is chosen by traversing (probabilistically) the equipment hierarchy.