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 3.6e Defenses
Alright, so I'm one of those guys who thinks 4e is garbage. However, I do like some parts of 4e, and I aim to make a set of variant rules based on concepts introduced in 4e. This page is a variant rule for modified defenses. But first, some history...
In early editions of DnD you needed an elaborate tables and a degree in mathematics to understand THAC0. 3.0 was released and with it, a modified version of Armor classes. Suddenly it made sense. Big numbers were good, small numbers were bad. Children could suddenly understand the game. In June of 2008 4e was released, and there was a massive wave of criticism about dumbing down the game, and cutting out DnD's soul, and other silly things. I'll admit (again), I don't like 4e. However, I do like the defense system. Below is my new system for defenses in DnD.
 The Variant Rule
 The Basics
When you're on the defense, you don't ever have to roll the dice. That's the plan. When you're doing the attacking, you have to make the attack rolls. Here's how we do it:
- Armor class is unchanged.
- Add a +10 to all three saves (Fortitude, Reflex, and Will), but you no longer roll 1d20.
Calm down, it's not that exciting. Normal attacks made against AC (that is, melee and ranged attacks, the sort of things most people do) go unchanged. The term "Saving Throw" gets thrown away. Spells, and other effects, that normally require a saving throw now instead must make an "attack roll" against your F/R/W defense. The "attack roll" is simply associated ability modifier+Spell Level+1d20. You must make an attack roll for every creature in your spells area, friend or foe. Let's see if that makes sense.
 An Example
Tordek and Hennet get into a bar fight. Hennet, the sorcerer, turns on a very drunk Tordek and casts fireball. Hennet's Charisma is 17, and Fireball is a 3rd level spell. Therefore, the attack roll is 1d20+3(from charisma)+3(spell level). Hennet rolls an 11, giving him a total of 11+3+3=17. Tordek, who isn't normally a very agile fellow, has a Reflex defense of 4(Base reflex modifier)+1(from dexterity)+10(as per the new rule), so 4+1+10=15. Tordek is toast! Oh noes, Johannes, the Barkeep, was also caught in the blast! Hennet must also make an attack roll against Johannes' reflex defense. Hennet rolls a 19, giving him 19+3+3=25! Johannes, being a commoner, has a reflex defense of only 2(base)+1(dexterity modifier)+10(as per the new rule). That's Hennet's 25 vs Johannes' 13. Someone should tell Johannes' wife he won't be coming home tonight...
 Critical hits
|“||Ooh, attack rolls mean critical threats. Critical fireballs make me happy. Very Happy.||”|
|—Munchkins across the world|
Sorry, no critical hits on spells yet. I have to crunch the numbers more to decide if they would be over powered or not. Currently it looks like you won't be dealing double damage. However, A natural 1 (the d20 comes up 1) on an attack roll is always a failure. A natural 20 (the d20 comes up 20) is always a success, and the spell may cause damage to exposed items (see Items Breaking after a Saving Throw, below).
 Items Breaking after a Saving Throw
Unless the descriptive text for the spell specifies otherwise, all items carried or worn by a creature are assumed to survive a magical attack. If a caster rolls a natural 20 on its attack roll however, an exposed item is harmed (if the attack can harm objects). Refer to Table 10–1: Items Affected by Magical Attacks, in the Player's Handbook. Determine which four objects carried or worn by the creature are most likely to be affected and roll randomly among them. The caster then makes another attack roll, and deals damage accordingly (see Smashing an Object, on page 165 of the Player's Handbook). For instance, Tordek is hit by a lightning bolt, and the caster gets a natural 20 on his attack roll. The items of his most likely to have been affected are his shield, his armor, his waraxe (in his hand), and his shortbow (stowed). He doesn’t have magic headgear or a magic cloak, so those entries are skipped. If an item is not carried or worn and is not magical, it simply is dealt the appropriate damage.
 Why is this any good?
 Player's Viewpoint
Statistically, this is pretty much the same. However, player's might like it because it "puts the power back in the hands of the player". It's a tense moment when the wizard casts fireball, and you hope the dragon fails his save. Everyone eagerly awaits the roll, praying for a low number. In the new system the wizard is the one rolling the die. The fate of his party, and perhaps the world, rests in his quivering palm. He's the one the party is looking to, he might as well be the one rolling the dice.
 DMs Viewpoint
You have a tough job as it is. No more rolling dice except when it's the monster's turn to attack. Simply add 10 to the numbers in the Monster Manual and you're good to go. If you want to be very theatric, you can even tell your players exactly what they need to roll to hit you, and smirk as their jaws hit the table. Let's the players have some fun, how often does a wizard get to roll a d20 anyway?
 Closing Notes
Everything still works just as it did before, beyond what is mentioned here. Cloaks of Charisma still add to your charisma score, which will add to the attack roll of sorcerers, and cloaks of resistance will still add to the save defenses of anyone who wears one. Poisons, and other things, that normally have a set DC for fortitude, or other, saves are the only hiccup. Just subtract 10 from the printed DC, and then add 1d20 to what is left as the poison's "attack" against the player.