Do special abilities and wonderous items with similar effects cumulate

dnd-3.5emonkstacking

Our monk's build contains various abilities and items that, in part, give him the same bonus, I am not sure if all of them would accumulate or not.

  1. Item: Monk's Belt (DMG 248)

This simple rope belt, when wrapped around a character’s waist, confers great ability in unarmed combat. The wearer’s AC and unarmed damage is treated as a monk of five levels higher. If donned by a character with the Stunning Fist feat, the belt lets her make one additional stunning attack per day. If the character is not a monk, she gains the AC and unarmed damage of a 5th-level monk. This AC bonus functions just like the monk’s AC bonus.

  1. Extraordinary Ability: Unarmed Damage (Fist of Forest -complete champion 81)

Your unarmed attacks deal more damage than usual. At 1st level, you
deal 1d8 points of damage with each unarmed strike. When you attain
3rd level, this damage increases to 1d10 points. See the monk class
feature (PH 41). If your unarmed attack already deals this amount of damage, increase the base damage to the next step indicated on the monk class table

  1. Supernatural ability: Morphic Weapons (Su) (warshaper – complete warrior pag 90)

As a move action, a warshaper can grow natural weapons such as claws or fangs, allowing a natural attack that deals the appropriate amount of damage according to the size of the new form (see Table 5–1 on page 296 of the Monster Manual). These morphic weapons need not be natural weapons that the creature already possesses. For example, a
warshaper polymorphed into an ettin (Large giant) could grow a claw
that deals 1d6 points of damage, or horns for a gore attack that deals 1d8 points of damage. If the warshaper’s form already has a natural weapon of that type, the weapon deals damage as if it were one category larger. For example, a warshaper who used wild shape to
become a dire wolf (Large animal) could grow its jaw and snout,
enabling a bite attack that deals 2d6 points of damage (as a for Huge animal), not the normal 1d8. A warshaper can change morphic weapons as often as it likes, even if it is using a shapechanging technique such as the polymorph spell or the wild shape class feature that doesn’t allow subsequent changes after the initial transformation.

  1. ITEM: gauntlet of the Talon (complete divine 97)

A character wearing gauntlets of the talon effectively has natural weapons that deal 1d8 points of slashing damage and count as magic for the purpose of overcoming damage reduction. If a monk dons the gauntlets of the talon, she is treated as if she were five levels higher for purposes of AC, unarmed damage (which now counts as slashing), and the monk’s ki strike ability (this function stacks with the similar functions of a monk’s belt). Gauntlets of the talon function as ghost touch weapons for the purpose of attacking incorporeal creatures. Finally, the wearer gains a +4 bonus on all grapple checks. To use this relic, you must worship Bahamut and either sacrifice a 4th-level divine spell slot or have the True Believer feat and at least 7 HD.

  1. Spell: Animal Growth
    a member of the party casts this on him when the monk uses his bear form (the monk has also the Prestige Class of "bear warrior")

Best Answer

Monking…

In this comment, the asker mentions that the characters in question are level 30. The rules for the Epic Monk, on Unarmed Strike say, "The damage for a monk’s unarmed strike does not increase after [20]th level" (Dungeon Master's Guide 208).1

In other words, a Medium creature that's effectively Mnk20+ insofar as unarmed strike is concerned sees that unarmed strike damage because of monk levels reach its peak at 2d10 points of damage. Another 5 levels from a monk's belt (DMG 248) (13,000 gp; 1 lb.) or 5 levels from gauntlets of the talon (Magic Item Compendium 103–4) (4,000 gp; 2 lbs.) or 10 levels from both doesn't allow exceeding that Medium Mnk20+'s 2d10 barrier.

Foresting…

The fist of the forest prestige class's unarmed damage class feature, in part, says, "If your unarmed attack already deals this amount of damage [i.e. 1d10 or, presumably, more], increase the base damage to the next step indicated on the monk class table" (Complete Champion 81), and the monk class table's unarmed strike damage doesn't extend past 20.

Nonetheless, a GM could extrapolate that table to accommodate the fist's damage. Table 2–2: Increasing Weapon Damage by Size (DMG 28) shows one way of advancing damage, saying that a weapon that normally deals 2d10 points of damage deals instead 4d8 points of damage if it's bigger—conveniently the same as a Large Mnk20's unarmed damage—, but be aware that the monk class table doesn't rigorously obey Table 2–2 (also see Bearing, below).2

Bearing…

If a Medium creature's unarmed strike damage is already the maximum it can be from the monk table, and the DM has not to extend the table (see Foresting, above), then becoming—via the bear warrior prestige class's bear form supernatural ability (Complete Warrior 16—17)—a brown bear or dire bear (both Large) will increase the creature's unarmed strike damage to that of a Large monk (see here) therefore from a former peak of 2d10 to a new peak of 4d8.

If, while using the bear form ability to assume the form of a Large bear, the once-Medium creature is subsequently the subject of the 5th-level Drd spell animal growth [trans] (Player's Handbook 198), then the creature is a Huge bear… with a Mnk20's unarmed strike. While no rules were published for a 3.5 Huge or bigger monk's unarmed strike, a reader can use Table 2–2 to determine that that going from a Medium Mnk20 to a Large Mnk20 yielded an unarmed strike that deals 4d8 points of damage, therefore going from a Medium Mnk20 to a Huge Mnk20 yields an unarmed strike that deals 6d8 points of damage.

…Then Morphing

"A monk’s unarmed strike is treated… as a manufactured weapon… for the purpose of spells and effects that enhance or improve… natural weapons," says the monk's unarmed strike class feature (PH 41). Thus the warshaper prestige class can use its morphic weapons supernatural ability on its unarmed strikes so that "the weapon deals damage as if it were one category larger" (Complete Warrior 90), therefore following the the rules for increasing damage as per Table 2—2: Increasing Weapon Damage by Size (see Foresting, above). Exercise caution with the morphic weapons ability, though, as it lends itself to controversy.3

Putting it all together

  • The unarmed strike of a Medium Mnk20+ (who is possibly black bear) deals 2d10 points of damage.
  • The unarmed strike of a Large Mnk20+ (whether a black bear with an animal growth spell or a brown or dire bear) deals 4d8 points of damage.
  • The unarmed strike of a Huge Mnk20+ (who is possibly a brown or dire bear with an animal growth spell) deals 6d8 points of damage.
  • The morphic weapons ability can increase each of previous by a total of just 1 step on Table 2–2 to from 2d10 to 4d8 or from 4d8 to 6d8 or, finally, from 6d8 to 8d8, respectively.

1 The DMG says 16th level; the SRD says 20th level. That's probably stealth errata on the SRD's part for a failure to update the DMG to match changes wrought by the 3.5 revision. (C.f. The DMG on Spell Resistance still using the spell power word stun as an example of a conjuration spells when the 3.5 revision made it an enchantment spell.)
2 Medium Monk unarmed strike damage goes from 1d6 at levels 1–3, 1d8 at 4–7, 1d10 at 8–11, 2d6 at 12–15, 2d8 at 16–19, and 2d10 at 20. Table 2–2 has a 1d6 weapon go to 1d8 at Large, 2d6 at Huge, 3d6 at Gargantuan, and 4d6 at Colossal.
3 For examples, see this 2005 EN World thread, this 2010 Giant in the Playground thread, and this 2012 Min/Max Boards thread.

Note: All that said, monks tend to need all the help they can get. And, technically, this isn't stacking but just a combination of abilities that may synergize.

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