How does the Power Critical feat work?

Question

Now in the Complete Warrior book for D&D edition 3.5, there is a feat called "Power Critical" (p. 103). Its description states:

When using the weapon you selected, you gain a +4 bonus on the roll to confirm a threat.

Now does that mean that if I was using, for example, a Greataxe and I rolled a base 16 on the die, it would equal a 20 for a critical? Or would it be a +4 on damage for a critical?

I may just be overlooking something but I can't seem to get the correct picture. An explanation would be great.

Answer 1

From the d20 SRD "Actions In Combat" page:

When you make an attack roll and get a natural 20 (the d20 shows 20), you hit regardless of your target’s Armor Class, and you have scored a threat. The hit might be a critical hit (or "crit"). To find out if it’s a critical hit, you immediately make a critical roll—another attack roll with all the same modifiers as the attack roll you just made. If the critical roll also results in a hit against the target’s AC, your original hit is a critical hit. (The critical roll just needs to hit to give you a crit. It doesn’t need to come up 20 again.) If the critical roll is a miss, then your hit is just a regular hit.

The feat gives you a +4 the critical roll to confirm the critical hit.

Following your example, if you roll a natural 20 with your greataxe, you'd score an automatic hit, and a critical threat. Going forward let's assume a +10 to hit and an AC of 20 on the target. You could then roll a critical roll at +14 (thanks to the feat) vs the AC of 20. If you roll a 6 or higher, you would score a critical hit.

Answer 2

When you roll a number in your critical threat range (usually a 20), you threaten a critical hit. Check under 'Critical Hits' here. Also see this question. You then have to make another attack roll to confirm the critical. This roll, in general, consists of d20 + any modifiers that applied to your original roll against the enemy AC. If you make the confirm roll, the attack is a critical and does double damage. If you fail the confirm roll, the attack still hits, but doesn't count as a critical. This feat provides a substantial bonus, but only on the confirm roll, not on the original roll.

In your specific example, if you rolled a 16 it would not be a critical. If you required a 20 to hit (hypothetically), then a 20 would threaten a critical. When you rolled to confirm without the feat, a 20 would be required to confirm the critical (since you required a 20 to hit). However when you rolled to confirm with the feat, only a 16 or higher would be required to confirm.