# Is the Keen enchantment better than an enhancement bonus on a rapier?

What weapon has a greater damage per attack: +1 Keen Rapier or +2 Rapier?

Here are the base numbers we can use:

STR 14
DEX 18 (uses Weapon Finesse for attack)
BAB +8
+1 Rapier Crit: 18/x2

Single Attack: +13
Single Damage: 1d6+3

Enemy AC: Since this depends on the target’s armor class, let’s evaluate for a range of enemy ACs. 15/20/25 should be enough to draw a conclusion.

Keen Weapons double the threat range, making the critical data for a rapier: 15/x2

Other considerations:

1. This doesn’t consider iterative attacks, calculating this is optional for me.
2. This is a warblade, and he gets +2 to confirm critical hits. I’m ok ignoring this calculation for now.
3. Without going into the wealth of strike maneuvers, obviously many of them deal a bunch of damage but don’t get multiplied on a critical hit.

So the question again: How does the increased threat range on a Keen rapier compare to an extra +1 enhancement enchantment?

• These calculations will depend on the AC of the target. Can you clarify how you'd like answers to address this? For example, can you provide a target AC? Or perhaps specify your character level, and request that answers calculate a target AC in some way, like averaging enemies of that CR in the Monster Manual? – A_S00 May 8 '19 at 21:33
• @A_S00 I’ll edit something in. – FrancisJohn May 8 '19 at 22:49
• How likely is it that you can obtain a Scabbard of Keen Edges? How likely are you to have a caster for Magic Weapon, Greater? – Matthieu M. May 11 '19 at 15:40
• @MatthieuM. I could get the item, but to me that doesn’t seem to be a cost effective choice. Probably not worth finding the spell either. I appreciate your outside the box answer though, thank you. – FrancisJohn May 11 '19 at 17:29

$$\\begin{array}{|c|c|c|} \hline \textbf{AC - BaseToHit} & \textbf{+2 dmg mults} & \textbf{keen dmg mults} \\ \hline \text{<=3} & \text{21.85} & \text{24.7} \\ \text{4} & \text{21.85} & \text{23.4} \\ \text{5} & \text{20.7} & \text{22.1} \\ \text{6} & \text{19.55} & \text{20.8} \\ \text{7} & \text{18.4} & \text{19.5} \\ \text{8} & \text{17.25} & \text{18.2} \\ \text{9} & \text{16.1} & \text{16.9} \\ \text{10} & \text{14.95} & \text{15.6} \\ \text{11} & \text{13.8} & \text{14.3} \\ \text{12} & \text{12.65} & \text{13} \\ \text{13} & \text{11.5} & \text{11.7} \\ \text{14} & \text{10.35} & \text{10.4} \\ \text{15} & \text{9.2} & \text{9.1} \\ \text{16} & \text{8.05} & \text{7.8} \\ \text{17} & \text{6.9} & \text{6.25} \\ \text{18} & \text{5.75} & \text{4.8} \\ \text{19} & \text{4.6} & \text{3.45} \\ \text{20} & \text{3.45} & \text{2.2} \\ \text{21} & \text{2.2} & \text{1.05} \\ \text{>=22} & \text{1.05} & \text{1.05} \\ \hline \end{array} \$$