For the first few encounters you come across, walking up and hitting your foes or shooting them from afar works fine as they are few in number and fairly weak. Surrounding an enemy actually provides you with a flanking bonus, allowing your characters to do more damage to them, so rushing in and wailing away makes perfect sense. All of that goes away fast, though, as every encounter after the first few “tutorial” ones will place you in situations where you’re outnumbered by at least three to one.The only way to a surefire victory is by combining magical effects.
See a pool of oil? Set it on fire to create a patch of burning ground that will constantly damage enemies walking over it and maybe even apply a “burning” effect that damages them further. Maybe throw some poison in there to create an explosion for a quick burst of damage and to clear the ground to make it safe for you and your allies. Few spells or abilities by themselves provide the “crowd control” options you find in other RPGs, but mixing and matching them helps to create favorable situations for your party. Casting a rain spell and then a freezing spell on a particularly difficult foe - or just freezing the ground beneath its feet so it slips and falls - can help ensure it stays out of combat for just enough turns to deal with other lesser threats.
Larian keeps things interesting, too, by varying the types of enemies - some of which are immune or resistant to different elements - and how they’re grouped up across an area. No battle is ever a guaranteed victory and you should be prepared to save and load your game quite often. That small group of enemies that appear to be an easy win may actually turn into a trap that places you into a much larger encounter.
Coming up with a strategy for dealing with those enemies, utilizing everyone’s skills, and making careful judgments about when to advance and when to hold back reminds me of just about every encounter I've faced in D&D games. What’s more, victory in Divinity: Original Sin by no means feels like a guarantee, but it always feels well-earned. Just as in D&D, too, your rewards for defeating your foes means more experience to help level up and it also means better gear. Much like action-RPGs, killing enemies and searching through lootable objects will yield gear that ranges in green uncommon to orange uniques. Unlike those games, don’t expect to see too much gear that boost your damage to such a degree that you walk on nothing but a carpet of fallen enemies. Boosts from these items offer slight increases to your attributes, your resistances, and may even give you points into your abilities, which will let you learn more skills in a particular melee/magic tree, but you’ll still need to treat every encounter like it could be your last.
From the turn-based combat to the immersive world and variety of NPCs, it’s easy to lose yourself in Divinity: Original Sin for a while. My biggest issue with the game thus far is the lack of explanation for some of the mechanics. The tutorial dungeon explains the general idea of how to interact with the world and do things like open locked chests or sneak, but after that you’re on your own to discover things.
For example, new skills aren’t learned automatically from levelling up. Instead, skill books are mainly acquired by bartering with a variety of NPCs. Once you see that’s how you get them, you start bartering with everyone you meet. Until that point, though, you might go for hours and through several levels wondering if your basic “poison arrow” spell is all you get. There’s also a crafting system in the game that lets you make your own arrows, spell scrolls, and even weapons and armor, but knowing how to make them comes from recipe books that are scattered throughout the game. These books will provide you with the ideas of “combine this and that to get this other thing,” but some of those recipes require other objects, like a stove or a campfire, that may lead you to wonder “well how do I make those” and it’s not until you stumble across one that you realize you’ll have to track them down.