[PF] Anyway to gain bonus damage by taking damage or losing hp/Con?

[cmdrsmushy]

I have this image in my head of my Magus actually killing herself trying to defeat her enemies.

So the question is, is there any means (feats, prestige classes, traits) to inflict damage to yourself to gain bonus damage?

Even if it is a home brew or 3rd party the Gm is pretty open to ideas as long as it is not broken.

[123456789blaaa]

There's the shocking fist feat in Player's Guide to Eberron, p. 151. It's Warforged exclusive though.

[NightbringerGGZ]

I have this image in my head of my Magus actually killing herself trying to defeat her enemies.

So the question is, is there any means (feats, prestige classes, traits) to inflict damage to yourself to gain bonus damage?

Even if it is a home brew or 3rd party the Gm is pretty open to ideas as long as it is not broken.

Tieflings have an archetype that does just this, the Fiend Flayer. You take 2 points of Con damage to restore 1 point in your Arcane Pool. If you use this ability, you can summon a magical weapon that gets free enhancement bonuses as you level up.

[Edge of Dreams]

A Vicious weapon (http://www.d20pfsrd.com/magic-items/magic-weapons/magic-weapon-special-abilities/vicious) deals an extra 2d6 damage to the foe and 1d6 to the wielder.

[Exirtadorri]

Im pretty sure there is a prc that gives you something similar. The ability is called stigmata.

[SamBurke]

The following Prestige Classes may help you:

Bloodmage (http://www.d20pfsrd.com/classes/prestige-classes/other-paizo/a-b/bloatmage)

Pain Taster (http://www.d20pfsrd.com/classes/prestige-classes/other-paizo/n-r/pain-taster)

Aaaaaand that's about all I got.

EDIT: Found that Stigmata thing.

It's in the Holy Vindicator PrC. (http://www.d20pfsrd.com/classes/prestige-classes/other-paizo/e-h/holy-vindicator)

[NightbringerGGZ]

Im pretty sure there is a prc that gives you something similar. The ability is called stigmata.

The Holy Vindicator. You have to have Channel Energy, cast 1st level divine spells and either Alignment Channel or Energy Channel. It doesn't work well for a Magus build, but it fits the character concept rather well.

[StreamOfTheSky]

It's technically AC penalties and not damage to self, but the increased hit % of foes makes it functionally the same....

Check out the Barbarian's Reckless Abandon and Come and Get Me rage powers. The former sacks AC for an attack bonus (which scales identically with power attack, hint hint), the latter sacks AC for the ability to pre-emptively AoO counterattack anyone that attacks you.

[Kuulvheysoon]

Blade of Blood, PHB2 (3.5e).

An extra d6 of damage, or 3d6 if you inflict 5 damage to yourself. It's on the duskblade spell list, the precursor to the Magus.

[Yogibear41]

HellFire Warlock Prestige class can choose to deal itself con damage to greatly increase the damage of an eldritch blast as well as to make a sort of flame shield that damages people who attack it, but its a warlock only prestige class.

[Big Fau]

This is the Crusader's entire purpose.

[TiaC]

The Lady's Gambit (http://www.realmshelps.net/cgi-bin/featbox.pl?feat=Lady~s_Gambit) feat does this.

[rot42]

Overchannel (http://www.d20pfsrd.com/psionics-unleashed/feats/overchannel-psionic) if you are psionic.

Bands of Blood Rage (MIC 202; 3.5) let you and willing allies enter a rage-like state while taking damage every turn.

Also in 3.5 (MoI 76) is the Lifebond Vestments soulmeld, which grants a lay on hands style ability that costs your own HP. Specifies living target, though, so no smacking undead with it without a houserule.

edit: Look for a copy of the BG thread (the site is currently down) "Naberius: sacking your stats for fun and profit".

[Kudaku]

Like has already been suggested, the Vicious enchantment lets you do +2d6 damage per swing but deals 1d6 damage to you as well.

This synergizes well with Magus, because of the gnome favored class bonus (http://www.d20pfsrd.com/races/core-races/gnome#TOC-Favored-Class-Options):
Magus Add one of the following weapon special abilities to the list of weapon special abilities the magus may add to his weapon using his arcane pool: defending, ghost touch, merciful, mighty cleaving, vicious; allying, conductive, corrosive, corrosive burst, menacing. Once an ability has been selected with this reward, it cannot be changed.

Basically you can use your arcane pool to enchant your weapon to do 2d6 extra damage to your target, but 1d6 damage to you.

If you're not playing a gnome, maybe you could ask your GM to allow you this one particular favored class option once and only for Vicious even if you're a different race?

[Zubrowka74]

If a feat can enable you to learn a caster's spells by drinking its blood then anything is possible.

[Slipperychicken]

In 3.5

The spell Masochism (Sorc/Wiz 2, Clr 3, some others 3) from BoVD gives you a bonus on attack and damage rolls scaling with the damage you take.

BoVD also has masochism as a character option (for free) on page 10. Masochists receive +1 to hit and damage rolls if they take their character level or more in damage in one round. Seems like it could be pretty significant at low levels. Sadism does the same thing, only for dealing damage. You don't even have to be Evil; a Paladin could easily be a sadomasochist.

There might be a feat for masochism too, but I can't find it.

[Mato]

3.5 also has Divine Sacrifice. Paladin 1st out of the SpC, during it's duration with any number of attacks you can choose to lose 2HP to deal an extra +1d6 damage with any melee attack, even stacks into it's self for up to +5d6 damage.