A New Critical House Rule

[Kaze Kyuubi]

So, by mistake my friend and I used the old version of criticals during our little trial dungeon the other day, his first day as the DM, and our first game with 4E. You know, 20 for a critical threat, roll again to see if you hit(still the same), but then we got it a bit mixed for how the new critical works because he hadn't read it properly. Apparently it just maxes your damage, but he thought it maxed the damage, and let you roll the die again, like how 3E let you roll an extra damage die or two.

Well, realising how much weaker a potential crit seemed, while more reliable, I also began looking at those feats and powers activated if you get a critical. So long story short, I realised, if the critical maxes your damage, then for the purpose of those abilities and feats, why not allow a perfect damage roll to count the same way? In other words, if you roll a d4 for damage, a 4 is considered a critical for the purpose of those abilities, and likewise, if you roll a d10, a 10 is considered a critical.

Now, this means a few things. First off, it means lower die damages have an easier time getting criticals than higher roll ones. I mean, that'd put a dagger at a 28.75% chance of getting a critical(5% from a d20 attack roll, 25% if it didn't crit already for the damage roll, so with diminishing returns...), while a Longbow woudl only have a 14.5% chance. That adds two things. First off, normally that'd be a 5% chance either way for both, so it's far higher, and makes those feats nicer to select. Second, it allows interesting options using weapons with low damage like the dagger to get the critical bonuses. I could see a Rogue specialising in that.

Anyway, what are you guys' thoughts on this idea? Good, bad?

 

[Wightbred]

You need to be very careful of the interaction between rules with something like this. 4e has lots of little effects that work off the rule base, and more are added all the time. If the rule means that a Rogue with a dagger can knock someone down 1 in 4 hits instead of 1 in 20, that could have a big impact on the effectiveness of the Rogue compared to other classes, which could really affect the balance.

We have a house rule similar to your initial mistake where if you max your damage and roll a crit you get to roll again and add (and roll again and add if this is max - ie: an open test). In reality this has only a minor effect on combat because it happens so rarely, but the theory that you can take out any sized solo with a single hit appeals to us.

 

[silverwhisper]

kaze, isn't this going to interact strangely with the high crit weapon property?

 

[Ceraus]

Well, realising how much weaker a potential crit seemed (...)

Criticals in 3.5 did double damage (triple if high crit).

Criticals in 4E do, on average, almost double damage (between double and triple if high crit).

However, in 3.5, it's pure double damage... 4E tends to average things. Criticals come from maxing the dice, yes, but also from a bonus given by almost all magic weapons.

Half of the "crit damage boost" comes from maxing the dice, which adds much more damage to high-damage-dice weapons and high-damage powers. (Also, "high crit" weapons add more damage dice.)

The other half of 4E's "crit damage boost" comes from magic weapons (and implements). They start with +1d6 on a critical and go up to +6d6. Weapon type and power damage has no effect, giving low-damage powers significant criticals but having less of an effect on high-damage powers. A small number of magic weapon properties add no critical or much more than 1d6.

Let's look at a few examples at low and high levels, with low-damage and high-damage weapons and using low-damage and high-damage powers. I'll use generic magic weapons with a normal critical; the last example will use a high crit 1d12 weapon with a high crit magic property.


Low-damage weapon

At low levels, with a +1 weapon, an attack that deals
1d4+5 damage (7.5 average) will deal
9+1d6 damage (12.5 average) on a crit. and

A powerful attack that deals
3d4+5 damage (12.5 average) will deal
17+1d6 damage (20.5 average) on a crit.

At high levels, with a +6 weapon, an attack that deals
2d4+18 damage (23 average) will deal
23+6d6 damage (44 average) on a crit.

A powerful attack that deals
6d4+18 damage (33 average) will deal
42+6d6 damage (63 average) on a crit.


High-damage weapon

At low levels, with a +1 weapon, an attack that deals
1d12+5 damage (11.5 average) will deal
17+1d6 damage (20.5 average) on a crit. and

A powerful power that deals
3d12+5 damage (24.5 average) will deal
41+1d6 damage (44.5 average) on a crit.

At high levels, with a +6 weapon, an attack that deals
2d12+18 damage (31 average) will deal
42+6d6 damage (63 average) on a crit.

A powerful power that deals
6d12+18 damage (57 average) will deal
90+6d6 damage (111 average) on a crit.


High-crit 1d8 weapon with a high-crit damage property

At low levels, with a +1 weapon, an attack that deals
1d8+5 damage (9.5 average) will deal
13+1d12+1d8 damage (24 average) on a crit. and

A powerful power that deals
3d8+5 damage (18.5 average) will deal
29+1d12+1d8 damage (40 average) on a crit.

At high levels, with a +6 weapon, an attack that deals
2d8+18 damage (27 average) will deal
34+6d12+3d8 damage (86.5 average) on a crit.

A powerful power that deals
6d8+18 damage (45 average) will deal
66+6d12+3d8 damage (118.5 average) on a crit.


I thought those damage values should be highlighted since you're new to the system and haven't seen many criticals in action. Once players get their greedy hand on magic weapons, critical hits go back to their 3.5 effectiveness.

No base weapon crits on a 18 or 19, but some class features and feats can allow it. Effective critical ranges are about half what they were, but without the confirmation roll, there's a similar critical rate in both editions.

Anyway, I think your house rule would break that delicate balance, especially in the way you suggest its implementation. 4E has many, many effects that take place only on a crit, like healing, moving and extra attacks, not to mention the debiliating effects. Players who want glorious criticals have many ways to get them.