I want to make a good melee build for this sword. I'm thinking dex build with mythic weapon finesse. Does that get the 1.5 dmg bonus still?

It should swap the stats, granted if you go fighter there is an ability that does that for you, saving you the feat. I forget what its called, but Regil has it on his standard build.

Make sure you have at least 13 str or 2 levels in ranger/slayer to get power attack so you can also get the +5 damage per 4 bab from mythic power attack

Really good question here, since I have always wanted to use that blade as well.
A couple of ideas off the top of my head:
-It probably doesn't matter if you go str or dex with it, but I would consider just going str for the extra feats you'll have (by not needing to take finesse feats).
-Rowdy rogue (or 1 level rowdy rogue dip) would give you vital strike for free, and you could take greater vital strike after that by somehow wrangling loremaster into your build. Additionally, rowdy rogue allows you to add 2d6 to your vital strikes for each d6 of sneak attack you have, so if you build as some kind of gish you can take the Sense Vitals spell for an extra 5d6 sneak when you want it.
-I can imagine attacking the boss, with a full attack, missing all the attacks, and hopefully racking up a decent hit bonus. (If you don't miss your attacks, then yay!). Next round, use greater vital strike, for a 4x damage attack that uses up the built up attack bonus and hopefully hits because of that. So basically my idea is that when the attack bonus is high, you can burn it with a massive vital strike.

Some ideas for the main part of the build:
-Magus (sword saint would be interesting) - you can use dimension strike/ prescient strike at the start of your turn to target touch/ flat-footed AC, making your big hit into a near certain thing. You won't get the Sense Vitals spell, unless you get to L19 in magus to take the bonus wizard spells. Also, side note, prescient strike effectively makes the enemy flat footed, so if you have some sneak attack it will be always active while prescient strike is on.
-Pure Rowdy Rogue for decent sneak attack, the rogue debuffs and rogue feats. Not my preferred choice because I like making gishes.
-Vivisectionist would be a nasty pick, since you have a free bite with feral mutagen, a full 10d6 sneak attack, mutagen for big stats and armor boost, and a bunch of utility including being able to cast a bunch of normally personal-only spells on allies (e.g. shield, true strike). Vivi 18, Rowdy 1, Loremaster 1.
-Arcane trickster with wizard - another option to stay a caster but stack up a bunch of sneak attack for your vital strikes. You'll have 1d6 from rogue dip, 5d6 from arcane trickster, and 5d6 from Sense vitals (and possibly 1d6 if you take accomplished sneak attacker, 1d6 if you wanted to waste the mythic feat, and then more if you take trickster mythic path). You would have Transformation if you wanted to go full front-liner. Wizard-of-choice-8, rowdy rogue 1, arcane trickster 10, loremaster 1. You'll have terrible BAB without a lot of buffs, but your sneak attack will be through the roof. Edit: You would also be a full caster and could specialize your caster side however you wanted, e.g. buffer, blaster, cc). You could make up for your lack of iterative attacks by taking gore from mythic path, bite from racial, and dipping something for another bite.

Some feats I would try and take:
-Mythic vital strike - necessary to make vital strike multiply the full damage from your hit.
-Power attack, mythic power attack - you want these for the damage boost that will multiply on your vital strike.
-Shatter Defenses - is very good, and might be worth it on this build, though not fully 100% committed since you're trying to be a big hitter and hopefully most things will die in one hit.
-Improved Critical, mythic improved critical - you want to crit as big as you can.

Some mythic paths that would be interesting to try:
If it's a main character, consider:
-Trickster path, gives you more sneak attack, and the ability to take special feats to get even more crit range and crit damage. You will also have access to a spell that makes you roll nat 20s on every roll for 3 turns (it's totally insane), meaning every hit/ vital strike will be a crit for the duration.
-Demon path - gives you a teleport that lets you teleport around the battlefield, and then vital strike on the same turn. Lets you make the most of each turn. No matter what path you take, it might be worth taking the demon (pre-)choice for mythic rank 1 and 2, since the extra gore will benefit from your sneak attacks (I think it's called close to the abyss?).
-Angel has a late ability called speed of light that will give you 2x extra attacks. Kind of useful for racking up the attack bonus from the weapon.

Race:
Consider taking something that gives a free bite, just because it will be an extra source of dealing sneak attack damage. These would be Motherless Tiefling, kitsune in fox form, or half orc with the racial feat you can pick.
If you don't want that, I would go human since you're going to need a ton of feats.

Anyway that's just off the top of my head and just some rough ideas.

I have a Skald in the group as well, for more bite attacks. Thanks for the ideas. The sword has always intrigued me and I haven't used it once.

Originally posted by Aussie 760:

It should swap the stats, granted if you go fighter there is an ability that does that for you, saving you the feat. I forget what its called, but Regil has it on his standard build.

Swap the stats in what way?

Originally posted by atm:

Really good question here, since I have always wanted to use that blade as well.
A couple of ideas off the top of my head:
-It probably doesn't matter if you go str or dex with it, but I would consider just going str for the extra feats you'll have (by not needing to take finesse feats).
-Rowdy rogue (or 1 level rowdy rogue dip) would give you vital strike for free, and you could take greater vital strike after that by somehow wrangling loremaster into your build. Additionally, rowdy rogue allows you to add 2d6 to your vital strikes for each d6 of sneak attack you have, so if you build as some kind of gish you can take the Sense Vitals spell for an extra 5d6 sneak when you want it.
-I can imagine attacking the boss, with a full attack, missing all the attacks, and hopefully racking up a decent hit bonus. (If you don't miss your attacks, then yay!). Next round, use greater vital strike, for a 4x damage attack that uses up the built up attack bonus and hopefully hits because of that. So basically my idea is that when the attack bonus is high, you can burn it with a massive vital strike.

Some ideas for the main part of the build:
-Magus (sword saint would be interesting) - you can use dimension strike/ prescient strike at the start of your turn to target touch/ flat-footed AC, making your big hit into a near certain thing. You won't get the Sense Vitals spell, unless you get to L19 in magus to take the bonus wizard spells. Also, side note, prescient strike effectively makes the enemy flat footed, so if you have some sneak attack it will be always active while prescient strike is on.
-Pure Rowdy Rogue for decent sneak attack, the rogue debuffs and rogue feats. Not my preferred choice because I like making gishes.
-Vivisectionist would be a nasty pick, since you have a free bite with feral mutagen, a full 10d6 sneak attack, mutagen for big stats and armor boost, and a bunch of utility including being able to cast a bunch of normally personal-only spells on allies (e.g. shield, true strike). Vivi 18, Rowdy 1, Loremaster 1.
-Arcane trickster with wizard - another option to stay a caster but stack up a bunch of sneak attack for your vital strikes. You'll have 1d6 from rogue dip, 5d6 from arcane trickster, and 5d6 from Sense vitals (and possibly 1d6 if you take accomplished sneak attacker, 1d6 if you wanted to waste the mythic feat, and then more if you take trickster mythic path). You would have Transformation if you wanted to go full front-liner. Wizard-of-choice-8, rowdy rogue 1, arcane trickster 10, loremaster 1. You'll have terrible BAB without a lot of buffs, but your sneak attack will be through the roof. Edit: You would also be a full caster and could specialize your caster side however you wanted, e.g. buffer, blaster, cc). You could make up for your lack of iterative attacks by taking gore from mythic path, bite from racial, and dipping something for another bite.

Some feats I would try and take:
-Mythic vital strike - necessary to make vital strike multiply the full damage from your hit.
-Power attack, mythic power attack - you want these for the damage boost that will multiply on your vital strike.
-Shatter Defenses - is very good, and might be worth it on this build, though not fully 100% committed since you're trying to be a big hitter and hopefully most things will die in one hit.
-Improved Critical, mythic improved critical - you want to crit as big as you can.

Some mythic paths that would be interesting to try:
If it's a main character, consider:
-Trickster path, gives you more sneak attack, and the ability to take special feats to get even more crit range and crit damage. You will also have access to a spell that makes you roll nat 20s on every roll for 3 turns (it's totally insane), meaning every hit/ vital strike will be a crit for the duration.
-Demon path - gives you a teleport that lets you teleport around the battlefield, and then vital strike on the same turn. Lets you make the most of each turn. No matter what path you take, it might be worth taking the demon (pre-)choice for mythic rank 1 and 2, since the extra gore will benefit from your sneak attacks (I think it's called close to the abyss?).
-Angel has a late ability called speed of light that will give you 2x extra attacks. Kind of useful for racking up the attack bonus from the weapon.

Race:
Consider taking something that gives a free bite, just because it will be an extra source of dealing sneak attack damage. These would be Motherless Tiefling, kitsune in fox form, or half orc with the racial feat you can pick.
If you don't want that, I would go human since you're going to need a ton of feats.

Anyway that's just off the top of my head and just some rough ideas.

I am trying out the viva/rowdy build. I couldn't get the prestige class to fit. Is it worth advancing sneak attack beyond the first feat? I am currently using 3 cleave feats and mythic power attack. Having fun so far.

dex to dmg for 2handers is only possible with 3 lvls of rogue.
better go str to get the 1.5 and save up on feats, like with a mutation warrior.

Originally posted by razvedchiki:

dex to dmg for 2handers is only possible with 3 lvls of rogue.
better go str to get the 1.5 and save up on feats, like with a mutation warrior.

I'm using viva with one dip in rogue. Is mutation warrior better?

Originally posted by Phil85:

Originally posted by razvedchiki:

dex to dmg for 2handers is only possible with 3 lvls of rogue.
better go str to get the 1.5 and save up on feats, like with a mutation warrior.

I'm using viva with one dip in rogue. Is mutation warrior better?

You can get DEX to DMG via fighter only feet (something finess). So Mutation warrior would be fine. Other wise use the mythic feat - does the same thing.

It's weapon finesse and mythic weapon finesse. It has to be used with a weapon with weapon finesse. It's two extra feats. I was wondering if using a mutation warrior and 1 rowdy rogue would be a better build then a viva and 1 rowdy rogue.

I would stick with Vivi-rowdy, since the rowdy is converting your sneak attacks to a large damage boost on vital strikes. You'll be missing a lot of the sneak attack if you go mutation warrior.
Vivi is such an awesome class :D Another definite benefit to being vivisectionist is that you can cast true strike on both yourself and others (with the infusion discovery). For very tough bosses, you can cast a quickened true strike before each vital strike, for +20 to hit.
My bad if loremaster doesn't go with alchemist - I guess you can't take metamagic with infusions? (??) Two solutions come to mind:

-Try rowdy 1, vivi 9, slayer of choice 10 (deliverer can be fun, although with mythic feats its 2d6 divine damage per hit is a bit paltry in WotR). The slayer gives you more sneak attack, and getting to L10 will give you one advanced rogue talent, which could be something nice like opportunist. The side effect is that your BAB will probably (?) be high enough for you to take Greater Vital Strike by end level. (IIRC you need 16 so 10 from deliverer, and you'd have 6 from vivi - tight but might be possible??) Also, you'll get studied target, for even more attack bonus.

-Or for a more caster take, try rowdy 1, vivi 7, bard 11, loremaster 1. You'd get the bard song to +3, so +3 attack and damage for your whole party, you would have access to the Sense Vitals spell and mirror image, you'd still be getting most of your bonus feats. If you are using greater enduring spells, as long as your x-minutes buffs are being cast at level 5, they will last 24h so it won't matter if your caster level is kind of low.

Originally posted by atm:

I would stick with Vivi-rowdy, since the rowdy is converting your sneak attacks to a large damage boost on vital strikes. You'll be missing a lot of the sneak attack if you go mutation warrior.
Vivi is such an awesome class :D Another definite benefit to being vivisectionist is that you can cast true strike on both yourself and others (with the infusion discovery). For very tough bosses, you can cast a quickened true strike before each vital strike, for +20 to hit.
My bad if loremaster doesn't go with alchemist - I guess you can't take metamagic with infusions? (??) Two solutions come to mind:

-Try rowdy 1, vivi 9, slayer of choice 10 (deliverer can be fun, although with mythic feats its 2d6 divine damage per hit is a bit paltry in WotR). The slayer gives you more sneak attack, and getting to L10 will give you one advanced rogue talent, which could be something nice like opportunist. The side effect is that your BAB will probably (?) be high enough for you to take Greater Vital Strike by end level. (IIRC you need 16 so 10 from deliverer, and you'd have 6 from vivi - tight but might be possible??) Also, you'll get studied target, for even more attack bonus.

-Or for a more caster take, try rowdy 1, vivi 7, bard 11, loremaster 1. You'd get the bard song to +3, so +3 attack and damage for your whole party, you would have access to the Sense Vitals spell and mirror image, you'd still be getting most of your bonus feats. If you are using greater enduring spells, as long as your x-minutes buffs are being cast at level 5, they will last 24h so it won't matter if your caster level is kind of low.

Thanks for the input. I have a few questions:
1. which feats do I need on the vivi to get true strike as a quickened move on my party? That would be nice.
2. How many sneak attack feats should I take? I didn't take any extra ones, but have the base rowdy ability.
3. I didn't extensively try to work in the loremaster. I saw it required 1 or 2 divine spells and two metamagic feats. I had trouble finding a devine spell on my vivi/rogue. Did I miss something? Is it worth two feats for that?
4. If I go mutation warrior/ rowdy, would that be better due to more feats?

1 - I believe you want to take an alchemist discovery called 'infusion', which allows you to cast any and all of your alchemist spells on party members. I believe there is also a mythic ability that then also extends the range so you can do it at range. (Can't remember the name for it). I had thought it was possible to use metamagic with alchemist spells... Just checked and it looks like you can take it on character creation, so just take quicken metamagic to be able to cast true strike quickened. There are also rods that can quicken a certain number of spells per day.

2 - Vivisectionist gets 10d6 sneak, which is plenty. I think sneak attack itself says you can't have more than that from your classes, (but adding more from Sense Vitals, mythic path, etc is fine), so no need to try get more than 10. I probably wouldn't even bother with accomplished sneak attacker unless I was only dipping shallowly into vivi/ rowdy.

3 - Loremaster requires you to be able to cast 3rd level divine or arcane spells, (either qualifies), know a metamagic, and have skill focus in knowledge arcana or world. I can't recalled trying to do it from an alchemist though, which I had thought was an arcane caster (they have a lot of the same spells as arcane casters) but might not qualify if they don't count as casting spells but using potions or something instead.
Loremaster lets you take a 'fighter secret', which can be pretty much any combat feat in the entire game, including a couple of the ones that are secret to the trickster mythic path ('improved improved critical' etc). You can take Greater Vital Strike if you a building for vital strike, and it will get around the fact that you won't reach BAB 16 as a prerequisite. You also don't need improved vital strike, as you normally would, and you can jump straight to greater this way.
You can also take a 'rogue secret' from it, which can be an advanced rogue talent, like opportunist, or the talent that drains the enemy's strength when you sneak attack them.
It also levels up your spellcasting from your base class so you don't loose any spell slots or caster levels for dipping loremaster. (I work Loremaster in to a lot of builds :D)

4 - Been a while since I played mutation warrior. It is quite a different route and you will get your damage in different ways (weapon specialization, weapon training, etc.) As far as feats go, you probably won't have as many more as you might think, since vivisectionist can take combat tricks for his medical discoveries, which means any time you get a medical discovery you can swap it out for a combat feat via combat trick, and you get medical discoveries every other level just as fighters get bonus feats every other level. Fighters are pretty fun, but hopefully someone who plays them more can give you some tips on how to build for a vital stiker on a fighter.

Good luck!

Or charge with mounted kitsune/barbarian with greater beast totem.

Originally posted by atm:

1 - I believe you want to take an alchemist discovery called 'infusion', which allows you to cast any and all of your alchemist spells on party members. I believe there is also a mythic ability that then also extends the range so you can do it at range. (Can't remember the name for it). I had thought it was possible to use metamagic with alchemist spells... Just checked and it looks like you can take it on character creation, so just take quicken metamagic to be able to cast true strike quickened. There are also rods that can quicken a certain number of spells per day.

2 - Vivisectionist gets 10d6 sneak, which is plenty. I think sneak attack itself says you can't have more than that from your classes, (but adding more from Sense Vitals, mythic path, etc is fine), so no need to try get more than 10. I probably wouldn't even bother with accomplished sneak attacker unless I was only dipping shallowly into vivi/ rowdy.

3 - Loremaster requires you to be able to cast 3rd level divine or arcane spells, (either qualifies), know a metamagic, and have skill focus in knowledge arcana or world. I can't recalled trying to do it from an alchemist though, which I had thought was an arcane caster (they have a lot of the same spells as arcane casters) but might not qualify if they don't count as casting spells but using potions or something instead.
Loremaster lets you take a 'fighter secret', which can be pretty much any combat feat in the entire game, including a couple of the ones that are secret to the trickster mythic path ('improved improved critical' etc). You can take Greater Vital Strike if you a building for vital strike, and it will get around the fact that you won't reach BAB 16 as a prerequisite. You also don't need improved vital strike, as you normally would, and you can jump straight to greater this way.
You can also take a 'rogue secret' from it, which can be an advanced rogue talent, like opportunist, or the talent that drains the enemy's strength when you sneak attack them.
It also levels up your spellcasting from your base class so you don't loose any spell slots or caster levels for dipping loremaster. (I work Loremaster in to a lot of builds :D)

4 - Been a while since I played mutation warrior. It is quite a different route and you will get your damage in different ways (weapon specialization, weapon training, etc.) As far as feats go, you probably won't have as many more as you might think, since vivisectionist can take combat tricks for his medical discoveries, which means any time you get a medical discovery you can swap it out for a combat feat via combat trick, and you get medical discoveries every other level just as fighters get bonus feats every other level. Fighters are pretty fun, but hopefully someone who plays them more can give you some tips on how to build for a vital stiker on a fighter.

Good luck!

Thanks for your help. I'm still trying to work in the Lormaster. Other than taking a 3 level dip in an arcane or divine caster, what else can I do to get those level 3 arcane or devine spells?