ExploderWizard
Hero
The problem is that if you don't remove backstab immunity for undead an undead themed adventure can easily become boring and frustrating for a rogue's player. Things like flavor or immersion are utterly pointless and even worse destructive to the game as a whole when they make the game boring or frustrating.
The thief was originally a third tier combat class behind the fighter and cleric. Every edition, the class has climbed higher up the combat heirarchy until it reached ninja status in 4E. Roles became so reversed that the fighter became the distraction, the pile of meat for things to pound on, while the ninja rogue cut it to pieces. Why does it make sense that a person who sneaks and steals as a specialty knows better where and how to strike than a dedicated warrior? Might as well just make the rogue a warrior class because as it stands, the fighter is just a grunt soldier and the rogue is a special ops expert.
Things that are traditionally immune to backstab tend to make for poor roleplaying encounters.
Does.....not.....compute. How does a creature's vulnerability, or lack thereof, to backstab matter with regard to interacting with it in a roleplaying capacity? " Sorry Count Bloodsucker I just can't negotiate with you. Your immunity to backstab is souring this whole conversation."
Is disappointment acceptable, though? I think it depends on the person you ask. Heroes in movies and books almost never find a situation where they aren't badass. They might find an enemy that is immune to one of their attacks, but they simply switch to another one and continue to be badass. They are heroes and they always find a way around any immunity the enemy has.
As the article says, sometimes being TOO realistic or immersive becomes a problem for fun, so you need to find a balance between the two. By defining things too narrowly, you are creating a situation that requires a player to be disappointed when if you had defined the ability slightly more broadly you wouldn't have to make the player disappointed.
If you begin with the assumption that all D&D adventurers are heroes (or want to be heroes) in the first place, then you are bound to run into problems. When playing a game you win some you lose some. The concept of playing a game in which there can be no loss (or dissappointment) is baffling. Just say "You are the heroes, you win" and call it a day.
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