P.Atk.

P.Atk.

P.Atk. = (Weapon P.Atk.*Level Modifier*STR Modifier*Mastery Modifier*Armor Bonus*M.Def. Bonus*Buffs Type 1)+Weapon Mastery+Buffs Type 2+Weapon Bonus
The final P.Atk. is rounded down.
Still no information on how Weaon SAs apply on P.Atk.

Weapon P.Atk.

type	P.Atk.
Fighter	4
Mystic	3

Level Modifier

(level+89)/100

STR Modifier

STR	modifier	STR	modifier	STR	modifier
1	0.30	18	0.55	35	1.01
2	0.31	19	0.57	36	1.04
3	0.32	20	0.59	37	1.08
4	0.34	21	0.61	38	1.12
5	0.35	22	0.63	39	1.16
6	0.36	23	0.66	40	1.20
7	0.37	24	0.68	41	1.24
8	0.39	25	0.71	42	1.29
9	0.40	26	0.73	43	1.33
10	0.42	27	0.76	44	1.38
11	0.43	28	0.78	45	1.43
12	0.45	29	0.81	46	1.48
13	0.46	30	0.84	47	1.54
14	0.48	31	0.87	48	1.59
15	0.50	32	0.90	49	1.65
16	0.51	33	0.94	50	1.71
17	0.53	34	0.97

Mastery Modifier

Do not use Mastery Modifier if you do not have any levels in Weapon Mastery.

Type	Formula
Fighter	1.085
Mystic	1.450

Armor Bonus

type	modifier
Doom light set	1.027
Nightmare Heavy set	1.04
Majestic Heavy set	1.04
Dark Crystal light set	1.04
Majestic light set	1.08
Draconic light set	1.04

M.Def. Bonus

type	modifier
Necklace of Valakas	1.04

Buffs/Debuffs/Toggles Type 1

If you have more than one of these, you multiply all of your buffs into the formula.
Please be aware of buffs that do not stack.

buff	lvl	modifier
Attack Aura	1	1.08
Attack Aura	2	1.12
Bear Spirit Totem	1	1.20
Berserker Spirit	1	1.05
Berserker Spirit	2	1.08
Bison Spirit Totem	1	1.43
Chant of Battle	1	1.08
Chant of Battle	2	1.12
Chant of Battle	3	1.15
Chant of Victory	1	1.10
Clan Might	1	1.03
Clan Might	2	1.05
Clan Might	3	1.06
Curse: Weakness	1	0.83
Curse: Weakness	2-5	0.80
Curse: Weakness	6+	0.77
Dance of Warrior	1	1.12
Demonic Blade Dance	1-3	0.9
Demonic Blade Dance	4-5	0.85
Demonic Blade Dance	6-7	0.8
Demonic Blade Dance	8-9	0.75
Demonic Blade Dance	10	0.70
Final Servitor	1	1.10
Frenzy (1hs/1hb/Pole)	1	2.00
Frenzy (1hs/1hb/Pole)	2	2.4976
Frenzy (1hs/1hb/Pole)	3	3.4638
Frenzy (2hs/2hb)	1	2.5026
Frenzy (2hs/2hb)	2	2.9955
Frenzy (2hs/2hb)	3	4.0195
Frenzy (other)	1-2	1.30
Frenzy (other)	3	1.50
Gift of Queen	1	1.06
Gift of Queen	2	1.08
Gift of Queen	3+	1.10
Greater Might	1	1.04
Greater Might	2	1.07
Greater Might	3	1.10
Herb of Strength	1	1.15
Howl	1+	0.77
Might	1	1.08
Might	2	1.12
Might	3	1.15
Mighty Servitor	1	1.08
Mighty Servitor	2	1.12
Mighty Servitor	3	1.15
Pa'agrian Gift	1	1.08
Pa'agrian Gift	2	1.12
Pa'agrian Gift	3	1.15
Poltergeist Cubic	1	0.77
Power Break	1-2	0.80
Power Break	3+	0.77
Prophecy of Fire	1	1.10
Rabbit Spirit Totem	1	0.70
Rage (1hs/1hb/Pole)	1	1.4520
Rage (1hs/1hb/Pole)	2	1.5486
Rage (2hs/2hb)	1	1.5536
Rage (2hs/2hb)	2	1.64085
Rage (other)	1-2	1.20
Rage of Pa'agrio	1	1.05
Rage of Pa'agrio	2	1.08
Sanctuary	1+	0.77
Seal of Despair	1	0.90
Stealth	1-3	0.55
War Chant	1	1.04
War Chant	2	1.07
War Chant	3	1.10
War Cry	1	1.20
War Cry	2	1.25
Warrior Servitor	1	1.10

Weapon Mastery

see here
don't forget that fighters have generic Weapon Mastery from being pre-20

Buffs/Debuffs/Toggles Type 2

buff	lvl	modifier
Archery	1	200
Assassination	1	70
Dead Eye	1	124
Dead Eye	2	134
Dead Eye	3	145
Dead Eye	4	155
Dead Eye	5	166
Dead Eye	6	177
Dead Eye	7	188
Dead Eye	8	199
Final Frenzy	1	32.9
Final Frenzy	2	39.4
Final Frenzy	3	46.6
Final Frenzy	4	54.6
Final Frenzy	5	63.3
Final Frenzy	6	72.7
Final Frenzy	7	79.3
Final Frenzy	8	86.1
Final Frenzy	9	93.1
Final Frenzy	10	100.2
Final Frenzy	11	107.5
Final Frenzy	12	114.8
Final Frenzy	13	122.1
Final Frenzy	14	129.3
Heroic Berserker	1	500
Heroic Valor	1	250
Master of Combat	1	80
Rapid Fire	1	62
Rapid Fire	2	67
Rapid Fire	3	73
Rapid Fire	4	78
Rapid Fire	5	83
Rapid Fire	6	89
Rapid Fire	7	94
Rapid Fire	8	100
Snipe	1	124
Snipe	2	134
Snipe	3	145
Snipe	4	155
Snipe	5	166
Snipe	6	177
Snipe	7	188
Snipe	8	199
Soul Cry	1	4.5
Soul Cry	2	14.0
Soul Cry	3	33.5
Soul Cry	4	66.5
Soul Cry	5	90.5
Soul Cry	6	141.5
Soul Cry	7	208.5
Soul Cry	8	247.0
Soul Cry	9	310.0
Soul Cry	10	375.5

Weapon Bonus

Weapon SAs actually add a decimal value to your patk despite what the in game descriptions say.
Critical Damage SA only adds to P.Atk. on a critical hit. There is still debate as to whether this SA is affected by buffs, critical buffs or soulshots.
I have no idea what's up with Critical Anger, I assume it works like Critical Damage.
*=I really doubt that's accurate.

type	modifier
Anger SA
Battle Axe	20.44
Blood Tornado	38.09
Deadman's Glory	30.12
Doom Crusher	11%*
Dwarven Hammer	26
Dwarven War Hammer	22.64
Elysian Axe	32.05
Great Axe	28.59
Heavy War Axe	28.59
Ice Storm Hammer	28
Lance	24.77
Orcish Glaive	20.44
Scorpion	24.77
Scythe	24.77
Silver Axe	20.44
Skull Graver	20.44
Tallum Blade	31.30
War Axe	24.77
Yaksa Mace	26.78

Critical Anger SA
Stormbringer	248.56

Critical Damage SA
Angel Slayer	265.00
Berserker Blade	269.91
Caliburs	213.12
Caliburs*Caliburs	127.00
Crystal Dagger	140.87
Dark Legion's Edge	326.28
Demon's Sword	159.93
Elven Sword*Elven Long Sword	61.40
Flamberge	174.78
Great Sword	247.98
Infernal Master	297
Infinity Cleaver	504.00
Katana	194.10
Katana*Raid Sword	84.11
Katana*Sword of Limit	146.88
Raid Sword*Sword of Limit	146.88
Samurai Longsword	231.29
Shamshir*Katana	84.11
Shamshir*Sword of Limit	146.88
Soul Seperator	200.79
Spirit Sword	194.10
Spirit Sword*Sword of Limit	146.88
Stormbringer*Shamshir	49.42
Stormbringer*Sword of Limit	166.26
Sword of Damascus	262.57
Sword of Delusion*Samurai Long Sword	133.97
Sword of Delusion*Sword of Nightmare	127.00
Sword of Limit*Sword of Limit	127.00
Tsurugi	213.12

Blunt Mastery Enchanted for Critical Damage

Works the same as Critical Damage SA

level	effect	level	effect	level	effect
1	113	11	252	21	390
2	127	12	266	22	404
3	141	13	279	23	418
4	155	14	293	24	432
5	169	15	307	25	445
6	183	16	321	26	459
7	196	17	335	27	473
8	210	18	349	28	487
9	224	19	362	29	501
10	238	20	376	30	515