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Mastering Magic

Building and Modifying Constructs

Source Ultimate Magic pg. 111
The Craft Construct feat allows a spellcaster to create all manner of permanent constructs in a process much like magic item creation. Each construct has a purchase price and a crafting cost, along with a list of requirements and the skills used to create them. Some require special materials in addition to the cost for basic crafting supplies, generally for the construct’s body. Special material costs increase both the purchase price and the crafting cost of the construct. The DC to craft a construct is 5 + the default caster level of the construct, just like for a magic item. Like when crafting magic items, a creator with a sufficiently high skill bonus may ignore these requirements. Each missing requirement increases the Craft DC by 5. Regardless, the creator must meet all item creation feats and minimum caster level requirements. Crafting a construct takes 1 day per 1,000 gp in the item’s base price, excluding any special material costs. This process is identical to the process for crafting a magic item, including the rules for accelerating creation and handling interruptions.

Animated Objects

Source Ultimate Magic pg. 111
Not all constructs are built with the Craft Construct feat. Spells like animate objects allow a caster to temporarily animate an existing object. These constructs are in many ways weaker than manufactured constructs, as they are susceptible to dispelling and antimagic.

A caster can use the animate objects spell to instantly create a temporary construct. A permanency spell cast upon an animated object makes the construct permanent; however, it can still be dispelled or suppressed by antimagic. Craft Construct creates permanent animated objects not susceptible to dispelling and antimagic. The CR of a potential animated object depends on its size and abilities, as explained in the animated object monster entry.

New Animated Object Abilities

Source Ultimate Magic pg. 111
The following are new abilities that can be applied to animated objects, whether created by the animate objects spell or with the Craft Constructs feat. Adding to these abilities requires the expenditure of Construction Points (CP), as described in the Animated Object monster entry.

Augmented Critical (Ex, 1 CP): Increase the threat range for the animated object’s melee attacks by 1 or the threat multiplier by 1. This cannot combine with itself or with the piercing attack or slashing attack object abilities.

Exceptional Reach (Ex, 1 CP): The object gains +5 feet of reach with one melee attack. Increase reach on all attacks for an additional +1 CP.

Improved Attack (Ex, 1 CP): All the animated object’s melee or ranged attacks do damage as though it were one size category larger. A crafter must purchase Improved Attack separately for melee and ranged attacks.

Piercing Attack (Ex, 1 CP): Replace one melee attack with an attack that does the same amount of piercing damage and has a ×3 multiplier. Replace all melee attacks for an additional +1 CP. Object abilities that specify slam attacks do not work on piercing attacks.

Ranged Attack (Ex, 2 CP): Replace one slam attack with a ranged attack. It does the same amount of damage, and has a range of 20 feet. Replace all attacks for an additional +2 CP. Object abilities that specify slam attacks do not work on ranged attacks.

Slashing Attack (Ex, 1 CP): Replace one slam attack with an attack that does slashing damage and has either a 19–20 threat range (for blade-like attacks) or a ×3 threat multiplier (for axe- or scythelike attacks). Replace all melee attacks for an additional +1 CP. Object abilities that specify slam attacks do not work on slashing attacks.

Trip (Ex, 2 CP): The object gains the trip special ability with one of its slam attacks.

Building New Constructs

Source Ultimate Magic pg. 111
Constructs typically have no Intelligence score, an average Wisdom score, and a Charisma of 1. Their dexterity is usually poor to average, though exceptionally nimble constructs do exist. Nearly all constructs of size Medium or larger have high Strength scores; constructs never have a Constitution score.

The monster creation rules in the Bestiary serve as your best guide for designing a new construct. New constructs should stick fairly close to the Monster Statistics by CR table found on page 291 of the Bestiary or the expanded table on page 293 of Bestiary 2. As they are usually mindless combat brutes, most use the “high attack” column, with damage falling in between the High and Low average damage columns. Note that all the construct’s saving throws are likely to be poor, and they have no favored saves. Lacking a Constitution score, a construct’s hit points also tend to be low in comparison to creatures with similar CRs. Consider giving any construct that doesn’t have either damage reduction or hardness a higher AC to compensate.

Pricing a New Construct

Source Ultimate Magic pg. 112
This section provides guidelines for those seeking to calculate the costs of crafting their own constructs. As a rough guideline, a construct’s price is equal to its challenge rating squared, then multiplied by 500 gp. Constructs with a fractional CR rating base their price on that fraction of 500 gp. For example, a CR 1/2 construct has a price of 250 gp. The cost of magical supplies for the Craft Construct feat is half this price, with the construct taking 1 day to create per 1,000 gp of the construct’s base price. Some constructs, particularly golems, have additional raw material costs that must be paid in full, regardless of whether the creator possesses the Craft Construct feat. Raw materials typically cost somewhere between 5% and 10% of the construct’s base price.

Constructs with multiple special abilities cost more to create. The first special ability is included in the construct’s base cost. The next two special abilities increase the calculated price by +1/2 CR per ability. Thereafter, any additional special abilities add +1 CR per ability. Examples of special abilities include having a higher DR value than a typical construct of its CR (above DR 5 for CRs 1–8, above DR 10 for CR 9+), monster statistics that exceed those recommended for the construct’s CR (see page 291 of the Bestiary), the standard golem immunity to magic, DR or hardness that can’t be overcome by all adamantine weapons, ability to be fully healed by a single spell, and most special attacks and special qualities.

Particularly powerful special abilities, such as an iron golem’s exceptionally high attack bonus, count as two lesser abilities. Animated objects are a special case— their base price is not increased by any abilities paid for with Construction Points (see the Animated Object monster entry), since these abilities are already factored into an animated object’s CR. In addition, golems and homunculi created with extra Hit Dice, the advanced template, or shield guardian abilities should all be priced as described in the Bestiary, rather than by adjusting pricing for their new CR.

Abilities that weaken or potentially place a construct at a disadvantage rarely reduce the construct’s price. An exception is the berserk ability. Constructs that have a chance of going berserk receive –1 CR adjustment to their calculated price if control can be reestablished (like a flesh golem) or –2 CR adjustment for permanent loss of control (like a clay golem).

The following is an example of the calculated costs for creating a stone golem (CR 11). A stone golem’s special abilities are golem immunity to magic, full healing from transmute mud to rock, a high to-hit bonus (+22 vs. the +19 typical for CR 11), and the ability to slow its foes. Further, since its spell vulnerabilities are not tied to common spells or effects, its immunity to magic cost is doubled, giving the stone golem a total of 5 special abilities. The first special ability doesn’t affect the cost, the next two increase the cost by +1/2 CR each, and the final two each increase the cost by +1 CR individually, making its effective CR for pricing equal to 14. This produces a calculated price of 98,000 gp, rounded up to an even 100,000 gp.

When designing a new construct, keep in mind that the above pricing formula only serves as a guideline. As with magic items, construct pricing remains more art than science, and like magic items, compare new constructs to existing ones for guidance. If you’re not sure, err on the side of a higher price.

Repairing Constructs

Source Ultimate Magic pg. 113
Even with the best of care, most constructs will eventually become damaged. Unless a construct suffers some sort of structural damage that radically alters its physical form, the construct continues to function at its full efficiency, and only falls apart once reduced to 0 hit points. Ideally, however, a construct should see some repair before it reaches that point. The make whole or rapid repair spells provide the easiest way to keep a construct in good condition. Both spells repair damaged constructs, even magic-immune ones like golems.

Failing that, a crafter can repair a construct with the Craft Construct feat. When repairing a construct, its master spends 100 gp per Hit Die of the construct, and then makes a skill check as if he were crafting the construct with a DC of 5 less than the DC for crafting that construct. With a success, the construct regains 1d6 hit points per Hit Die of the construct. Completing a repair takes 1 day per 1,000 gp spent on the repair (minimum of 1 day). Repair in this way can only be performed while the construct is inanimate or nonfunctioning. At any time, a construct’s creator can deactivate a construct under his control with a touch and a standard action.

A construct that has been completely destroyed cannot be repaired, though at the GM’s option some of the materials may be usable in the construction of a new construct. Additionally, some constructs have special means of repair, usually involving spells related to the golem’s nature (such as the use of acid damage to heal a clay golem.)

Construct Modifications

Source Ultimate Magic pg. 113
Standard constructs can be modified to enhance their base abilities, alter their appearance or function, or perform a variety of tasks beyond the intentions of their basic designs. Performing a modification provides a construct's creator with a simple way to create a unique construct. A modification can only be performed while the construct is inanimate or nonfunctioning.

Performing modifications on one's own construct requires the Craft Construct feat, and the creator must pay any additional crafting requirements and/or costs associated with the modification. Completing a modification requires 1 day per 1,000 gp of the modification's base price (minimum 1 day).

A list of all construct modifications can be found here.

Basic Modifications

Source Ultimate Magic pg. 113
These modifications are used to alter a construct’s basic properties: Armor Class, Hit Dice, and weaponry.

Armor Modification: This modification adds an enhancement bonus to the construct’s natural armor bonus or adds a magic armor property. The cost for magical enhancements equals the cost for creating magic armor as described in the Core Rulebook.

Hit Dice Modification: Hit Dice represent the overall strength and power of a construct. They affect a number of subsequent abilities, including hit points, saving throws, and base attacks. Determine the effects of a Hit Dice modification using the rules for adding creature Hit Dice on pages 290–291 of the Bestiary. Because a construct’s size is limited, a Hit Dice modification cannot increase its size. Therefore Hit Dice modification can never increase the base construct’s Hit Dice beyond 50% of its total HD. Some constructs have a defined cost for increasing Hit Dice. To calculate the cost per Hit Die of other constructs, divide the construct’s construction cost by its existing Hit Dice.

Weapon Modification: This modification enhances a construct’s physical weaponry. This process includes adding actual weapons (such as blades or spiked chains) to the physical structure of the construct or enhancing existing weapons with additional magical properties. Structural changes alter the construct’s damage only. A construct is automatically considered proficient with any weapon added to its structure as a weapon modification. The cost for adding a weapon is determined by the cost of the weapon or weapon enhancement added. The cost for magical enhancements to these weapons is the same as the cost for creating magic weapons as described on page 468 of the Core Rulebook. Performing a weapon modification also requires the Craft Magical Arms and Armor feat.

Ability Score Modification: Using this modification, a crafter can permanently increase one of the construct’s ability scores by +2 per modification. He cannot increase any abilities with a score of 0. The cost for permanently increasing an ability score is 5,000 gp.

Complex Modifications

Source Ultimate Magic pg. 114
These modifications represent more complex changes to the structure and function of the construct. The cost is equivalent to the minimum level to cast the spell × the spell level × 250 gp.