It almost feels like a lot of the non-D&D players are reading "Advantage" and "an Advantage" as the same thing, not realizing that "Advantage" is a specific, mechanical effect. From that fundamental misunderstanding of the rules, they construct entire edifices of reasons why getting advantage from Height/Backstab is good.
In previous editions of D&D there were dozens of different ways to get bonuses, and they would stack together to massively improve your odds of hitting. However counting all of this up, and making sure that you counted everything was time consuming, and tedious. This is why 5e does away with most of those things with just flat "advantage". The big change here is that ADVANTAGE DOES NOT STACK. Once you have advantage, getting it again is pointless. Moreover, Advantage and Disadvantage cancel each other out, regardless of how many stacks of one or the other that you have. This vastly simplifies combat in a way that speeds things up at the table. But this is not true when playing a CRPG.
It is for this reason that getting Advantage from height is bad, but getting an advantage is fine.
Turn based combat is an approximation, and one round is meant to happen all at the same time. This is why reactions exist, since everyone being paralyzed when it's not their turn becomes very silly very quickly. This is also why D&D uses Flanking and not Facing. The assumption is that your opponent has the ability to turn to face you as you circle around them, but once your buddy shows up, they can't face in two directions.
This is also the logic behind a rogue's sneak attack. They get sneak attack damage when they have advantage, or when an ally is adjacent to their target. That is, when their target can't give their full attention to preventing a more precise and thus dangerous attack. This is why attacking from stealth gives advantage, but just walking to an opponent's rear facing does not. The assumption is that any given character has their head on a swivel during combat. That they are aware of things all around them to simulate the ability to turn and look at something. It's why you can use a bluff check to pull an enemy's attention to get advantage.
The key difference between flanking and backstab is the need for a team mate. Many of the changes that Larian has made have reduced class specialization. Many of the Rogue's abilities have been given to everyone. Between flasks and special arrows being so common, and the fact that everyone can use scrolls with no penalty, there isn't really any need for party diversity.
The action economy of D&D is one that requires multiple encounters per day. Healing out of combat is a resource that dwindles. Resting is not free. The way spells recharge mean that magic is supposed to be powerful but limited, while weapon damage is reliable, and constant. The changes to accuracy changes the required hit points for enemies. Which changes the power of spells, which changes the action economy. Which changes the...
The D&D "purists" aren't saying that there should be no changes to the 5e rules. They are saying that every change has knock on effects that can't be ignored. If feels like they are being ignored right now.
Last edited by Paimon; 12/11/2007:10 PM. Reason: Typo