Gamasutra talked to the Systems Designer behind Divinity: Original Sin II's combat system.
The trouble with armor
DOS2’s combat design is a close evolution from 2014’s Divinity: Original Sin, but Larian Studios knew the original had some issues. The team liked the depth of its combat, but felt that it tipped the balance too far towards chaos. The problem was with its armor system.
Armor had the chance of blocking status effects, meaning that if you planned to knock a bunch of enemies out with a stun attack, you didn’t know for sure it’d work in every case. “The good part about this was that every encounter felt different, so when you started a fight it felt fresh. Things went wrong and right in very different ways,” says Pechenin. “But at the same time it really prevented long-term planning, because you didn’t know how many people you’d stun, so you couldn’t predict what you’d do next turn, and because of this you just wouldn’t think about the next turn.”
So one of the big changes to DOS2’s combat design was to its armor system. Rather than absorbing a proportion of incoming damage, armor completely negates it. There are two armor types: physical and magic, which negates any magical attack, including negative status effects. But as these values take damage they’re whittled down, and once gone, the character is left open to losing HP and vulnerable to status effects.
So far, so deterministic, but Larian wanted attacks to retain a ‘spicy’ feeling. The solution was a small variability in incoming damage which may entirely knock armor out, or it may not. “So there’s still some RNG there and you don’t know exactly how things will turn out, but you have a high chance that things will go as you want them to,” says Pechenin. “But at other times the game will throw a curve ball at you and make you scramble to find a new plan.”