Keen Rune limitations?

[Malagant]

So, I have been eyeballing the Earthbreaker for use with my Sparkling Targe Magus. It has some good utility and versatility which is of use to me. The Keen Rune is for slashing and piercing weapons, but an Earthbreaker can do Bludeoning or Piericng (Versatile P). If I were to put a Keen Rune on it, would the keen effect only apply to the piercing side or would it also work for the bludgeoning side? I'm still kinda new to pf2 and haven't seen anything to prevent it, but I could be missing something somewhere.

[Finoan]

Runes should apply to the entire weapon.

That is the benefit of Combination weapons instead of firearms with attached weapons like reinforced stocks and bayonets - that you only need one set of runes for the Combination weapon, but have to have separate runes for a firearm and its attached weaponry.

Do note the rules about Specific Magic Weapons. Initially I thought Earthbreaker was one - but it is just a standard weapon. You couldn't put a Keen rune on Blessed Reformer.

[Malagant]

Cool, thanks for clearing that up for me. :)

[Guntermench]

I don't think you can put Keen on an earthbreaker since it's base a bludgeoning weapon.

[Finoan]

That's a good point. I didn't check that.

[Guntermench]

If it was piercing with versatile bludgeoning this would work, but since it's the other way around I'm reasonably certain this does not.

[Castilliano]

If the rune were allowed (and I would allow it), it would only apply while using piercing, which IMO makes it a poor choice for runes.

[Finoan]

It feels ... strange ... to me that a bludgeoning (versatile piercing) weapon wouldn't work at all, but a piercing (versatile bludgeoning) weapon would work fully no matter what damage type it is dealing.

That is literally what the rules say. But I don't really like that answer.

Allowing the rune on a weapon that is capable of dealing the allowed damage types and only allowing it to apply when the weapon deals those damage types seems better even if it isn't strictly RAW.

[Super Zero]

That's how it works if you put it on handwraps of mighty blows. Seems like a reasonable ruling.

[nicholas storm]

Mathematically keen rune is a poor choice for a rune slot. You are better off not using it regardless of whether a weapon can use it or not.

[YuriP]

IMO.

RAW: You cannot use it in a weapon where the main damage doesn't qualify so once that Earthbreaker main damage is Bludgeoning this weapon doesn't qualify for rune activation. But if the weapon is a Slashing or Piercing damage with Versatile B like a Clockwork Macuahuitl you can use it for both damage types.

RAI: I don't think that designers really made some separated thing like main weapon damage type and versatile as secondary damage type in order to qualify to anything they probably choose betweem main and versatile damage at random. Also the Keen rune restriction to piercing and slashing damage is a question about thematic than mechanical (the idea is that your weapon is so magically sharped that it can do more critical damage with easy) so I don't think that forbids it to be applied and used in a bludeoning + versatile but that it will only work if you use the piercing or slashing of a weapon.

FoundryVTT: Similar to RAI. Foundry doesn't care about the Weapon type just about the damage that was being applied on the fly. So if you use the piercing and slashing part of any weapon with Keen rune it will give a critical if you hit with a 19 in a roll:

FoundryVTT's PF2e module - pf2e/src/module/item/physical/runes.ts version 6.0.4 automation, lines 1936-1954 wrote:

keen: {

attack: {
dosAdjustments: [
{
adjustments: { success: { label: "PF2E.WeaponPropertyRune.keen.Name", amount: "criticalSuccess" } },
predicate: new Predicate([
"check:total:natural:19",
{ or: ["item:damage:type:slashing", "item:damage:type:piercing"] },
]),
},
],
},
level: 13,
name: "PF2E.WeaponPropertyRune.keen.Name",
price: 3000,
rarity: "uncommon",
slug: "keen",
traits: ["magical"],
},

Balance: I don't see any balance problems in any way that you deal with the rune. Maybe Bludeoning damage with Keen will end being a very little bit more effective once the number os monsters with Bludeoning weakness and without Bludeoning resistance is greater can give a little advantage but this is a coincidence not a balance question also most of these bludeoning weak monsters are also immune to critical.

nicholas storm wrote:

Mathematically keen rune is a poor choice for a rune slot. You are better off not using it regardless of whether a weapon can use it or not.

Not exactly. Keen rune is bad vs targets that have low AC but pretty good vs target that have high AC like bosses this specially notable for classes that get a very high extra bonus like magus, barbarians and rogues.

For example lets consider these situations for a lvl 13 magus.

A target that you can hit rolling a 10 or more in an attack roll: No effect so use a property rune with a 1d6 energy damage is better.

A target that you can hit rolling a 11 or more in an attack roll:
Case 1: A 2 property energy damage runes (2d6) + 2-handed Greater Striking Earthbreaker (3d10) + Master Weapon Specialization (3) + Str (+4) + Gouging Claw SpellStrike (8d6 + 8 persistant) = AVG: 7 + 16,5 + 3 + 4 + 28 + 8persistant = 58,5 + 8persistant x hit rate (0,05 x success dice value + 0,05 due critical double damage) = (58,5 + 8persistant) x 0,55 = 32,174 + 4,4persistant
Case 2: A 1 property energy damage runes (1d6) + Keen rune + 2-handed Greater Striking Earthbreaker (3d10) + Master Weapon Specialization (3) + Str (+4) + Gouging Claw SpellStrike (8d6 + 8 persistant) = AVG: 3,5 + 16,5 + 3 + 4 + 28 + 8persistant = 55 + 8persistant x hit rate (0,05 x success dice value + 0,05 due critical double damage + 0,05 due critical double damage in a 19) = (55 + 8persistant) x 0,6 = 33 + 4,8persistant

A target that you can hit rolling a 15 or more in an attack roll:
Case 1: A 2 property energy damage runes (2d6) + 2-handed Greater Striking Earthbreaker (3d10) + Master Weapon Specialization (3) + Str (+4) + Gouging Claw SpellStrike (8d6 + 8 persistant) = AVG: 7 + 16,5 + 3 + 4 + 28 + 8persistant = 58,5 + 8persistant x hit rate (0,05 x success dice value + 0,05 due critical double damage) = (58,5 + 8persistant) x 0,35 = 20,475 + 2,8persistant
Case 2: A 1 property energy damage runes (1d6) + Keen rune + 2-handed Greater Striking Earthbreaker (3d10) + Master Weapon Specialization (3) + Str (+4) + Gouging Claw SpellStrike (8d6 + 8 persistant) = AVG: 3,5 + 16,5 + 3 + 4 + 28 + 8persistant = 55 + 8persistant x hit rate (0,05 x success dice value + 0,05 due critical double damage + 0,05 due critical double damage in a 19) = (55 + 8persistant) x 0,4 = 22 + 3,2persistant

A target that you can hit rolling a 19 or more in an attack roll:
Case 1: A 2 property energy damage runes (2d6) + 2-handed Greater Striking Earthbreaker (3d10) + Master Weapon Specialization (3) + Str (+4) + Gouging Claw SpellStrike (8d6 + 8 persistant) = AVG: 7 + 16,5 + 3 + 4 + 28 + 8persistant = 58,5 + 8persistant x hit rate (0,05 x success dice value + 0,05 due critical double damage) = (58,5 + 8persistant) x 0,15 = 8,775 + 1,2persistant
Case 2: A 1 property energy damage runes (1d6) + Keen rune + 2-handed Greater Striking Earthbreaker (3d10) + Master Weapon Specialization (3) + Str (+4) + Gouging Claw SpellStrike (8d6 + 8 persistant) = AVG: 3,5 + 16,5 + 3 + 4 + 28 + 8persistant = 55 + 8persistant x hit rate (0,05 x success dice value + 0,05 due critical double damage + 0,05 due critical double damage in a 19) = (55 + 8persistant) x 0,2 = 11 + 1,6persistant

So notice as more harder becomes to hit a target more efficient a Keen rune becomes once that it will hit a critical in a 19 doubling the damage. For other side it is useless if you already do a critical in 19 due hit vs AC difference. This make this rune more efficient vs stronger bosses but less vs minions but once that minions is already easier to deal, it's easier to notice how tempting is a keen rune over a damage property rune even if you know that's usually have a good number of minion in boss fights and mathematically if you count all your targets the property dmg rune is more efficient but for a class like a magus that have a high single target damage output they usually prefer to focus in more harder targets to avoid overkill so keen runes usually makes more sense for them.

[Malagant]

Finoan wrote:

That is literally what the rules say. But I don't really like that answer.

Where could I find the rule for this in the Player Core or GM Core?

[Malagant]

Next question. If you had the Savage Critical feat, would that stack with the Keen Rune? The phrasing doesn't seem to prevent it, IMO.

[shroudb]

Malagant wrote:

Next question. If you had the Savage Critical feat, would that stack with the Keen Rune? The phrasing doesn't seem to prevent it, IMO.

both make you crit on a "19 or higher".

it doesn't matter how many sources of that effect you have, since the effect offers a static number in both cases. so there's no stacking.

the wording, in order for it to stack, would have to be something like "reduce the number you need to crit by 1" or something along those lines.

[nicholas storm]

The math for keen for a reasonable situation:

Base to hit 9 on D20:

1 attack, no keen avg damage is 0.7xdamage of attack
1 attack, keen avg damage is 0.75xdamage of attack
Keen gives about a 7% increase in damage; to break even with a 1d6 rune, you need to do around 49 damage per attack.

2 attack, no keen avg damage is (0.7+0.4)x damage of attack
2 attack, no keen avg damage is (0.75+0.45)x damage of attack
keen gives about a 9% increase in damage; to break even with a 1d6 rune, you need to do around 35 damage per attack.

3 attack, no keen avg damage is (0.7+0.4+0.15)x damage of attack
3 attack, no keen avg damage is (0.75+0.45+0.2)x damage of attack
keen gives about a 12% increase in damage; to break even with a 1d6 rune, you need to do around 24.5 damage per attack.

So really keen does less damage than a 1d6 rune until high levels with lots of attacks per round.

And the guy who has a keen rune in one campaign I am playing forgets it, so it literally has added 0% damage for the entire campaign. When you use a VTT and don't roll dice, it's easy to not check a 19 roll.

[YuriP]

Malagant wrote:

Finoan wrote:

That is literally what the rules say. But I don't really like that answer.

Where could I find the rule for this in the Player Core or GM Core?

In the Weapons Statistics damage rule that states of type of weapon damage the weapon have. So if your weapon is a 1d10 B it's a bludgeoning while the Versatile trait give an alternate damage type that you weapon can deal but your weapon is still a weapon of the type that it was defined in the weapons table.

That said RAI I don't see any intention in the design of these weapons to forbid the keen rune not be used with the versatile damage type.

Malagant wrote:

Next question. If you had the Savage Critical feat, would that stack with the Keen Rune? The phrasing doesn't seem to prevent it, IMO.

No they doesn't stack their text says "you critically succeed if you roll a 19" not that you diminishes the NAT critical by 1.