Monster's defense vs. Player's defense

[CharlesPeter]

Please help...


Why is it that in the Moster Manual, monster's defenses are:

10 + half level + ability modifier + half level (again)

But in the player's handbook, player's defenses are:

10 + half level + ability modifer


Has anyone else noticed this? Why is this the case? Am I making a mistake? Am I supposed to calculate monsters and players defenses the same way?

Furthermore, this seems to make monsters really really hard to hit.

Please help, I am very confused.

 

[WOLead]

Because players get Enhancement Bonus and Armor Bonus to their AC to make up for the second half level that monster's get. NADs have a "Math Fix" feat to make up for the lack of scaling "armor" bonus that Armors get to keep up.

 

[CharlesPeter]

Is the enchantment bonus you mentioned just from enchanted armour, shields and items? Or is there another way to get it naturally?

 

[Neonchameleon]

Between levels 1 and 30, monsters get +29 to all defences - stats don't actually factor into monster defences other than setting the monster.

Between levels 1 and 29, PCs get
+15 (level) +6 (Enhancement bonus) + 3 (Feat - improved defences or weapon/implement expertise) + 5 (Stat - including the epic stat bumps) = +29.

Monsters are simpler because the DM needs to manage so many more of them and can't get to know them as well.

 

[the Jester]

A monster's defenses have nothing (well, very little) to do with their stats.

Monsters' defenses are set by role and level, and then tweaked to taste. For instance, a skirmisher's defenses are typically level + 14 (AC) and level + 12 (NADs).

 

[MatthewJHanson]

Is the enchantment bonus you mentioned just from enchanted armour, shields and items? Or is there another way to get it naturally?

For low magic settings there is the inherent bonus option presented in DMG 2 and Darksun Campaign Guide.

 

[UngeheuerLich]

There actually is a rule how monster defenses are calculated by its ability score.

A good rule of thumb however is increasing the defense where the monster has its best stats a bit and reducing the stats where the monster has bad stats a bit...

the average is level +12, but usually no monster actually hits it exacty.
(usually it is level +11/+12/+13 to the three different NADs)

 

[DracoSuave]

Also monsters start behind the curve for its defences but players get ahead very early and have easier access to reliable bonuses to hit and defense.

Then they got expertise.

Really though, you cannot meaningfully directly compare the stats of monsters and pcs and expect parity any more than you can compare a disposable razor to a proglide.

Monsters are designed to be disposable and wear down resources. Players are designed to destroy monsters and manage resources.
Theres numerical wiggle room there.

 

[Destil]

Monsters and PCs intentionality follow different rules, because they aren't designed to do the same thing.

Monsters are disposable and easy to run, because the DM has to handle 3-10 of them in most fights. They also, generally, lack non-encounter resources.

PCs are durable and very complex, because they are the stars of every fight (and have to survive several fights a day). They have non-encounter (i.e. daily and consumable) resources for tough moments and to help represent attrition.