El Mahdi
Muad'Dib of the Anauroch
Remember, in 3.x, the edition they're taking these backstab rules from...
Uhm, What?
The rogue in the current playtest document has sneak attack, and it’s a combination of the 3rd Edition and 4th Edition rules.
First, 3E did not have Backstab. A Rogue could only get Sneak Attack Damage if their target was denied their Dexterity bonus to AC, or Flanked.
There were no official facing rules in 3E, so there was no "behind the target" situation. In 3E, all combatants were considered to be moving about. There was only facing if the optional rules from Unearthed Arcana were used.
Second, 3E did not have Attack Advantage (which seems to be the same as 4E's Combat Advantage). 3E only had Flanking, which required another attacker besides the Rogue for a +2 to attack...or with Move Silently you could sneak up behind an enemy, and if you had a successful Listen vs. Move Silently skill check, then your target was denied their Dexterity to AC, and Sneak Attack Damage applied (but not a +2 to the attack for Flanking, unlike 4E's Combat Advantage). In 4E, you do get Combat Advantage for being behind a target (unable to see the attacker or unaware of the attacker).
The only real differences between the playtest version and the one presented in that blog is the inclusion of other classes being able to use it, the trading of your Combat Advantage Bonus (+2) for extra damage (Sneak Attack Damage), and the choice of the Rogue Class to use it or choose other Roguish attributes.
I don't understand this purposeful ignoring of the D&D Next designers usage of 4E elements. And especially don't understand how these same people can go on making claims that the designers are purposely not including elements of 4E (as you and others have said in other threads).
I'm truly baffled by this...