THE MECHA SUBTYPE
This subtype can be applied to any corporeal, mindless construct without the swarm subtype, granting it the following traits and abilities.
Operator Dependent (Ex): Constructs with the mecha subtype possess a low base attack bonus progression for their racial Hit Dice.
Hollow Shell (Ex): Constructs with the mecha subtype do not gain extra hit points based on their size.
Engulf (Ex): A construct with the mecha subtype is relatively hollow, using artificial gravitational forces and ablative layers of stabilized protomatter to insulate and suspend what it carries inside. This construct weighs significantly less than others of its kind, and may be commanded by an authorized user to target and engulf a creature of its size or smaller. If the targeted creature is willing, then the construct may engulf it as part of a move action. If the targeted creature is unwilling, the construct must hit with a melee touch attack that does not provoke an attack of opportunity. If it succeeds, the construct may then grapple and try to pin the creature. If a targeted creature finds itself pinned by the construct at the start of the construct's turn, it is engulfed by the construct and becomes its occupant. Any objects carried by the occupant that won't fit inside the construct itself, wind up in the construct's space.
Morphic Form (Ex): While it is occupied by a creature of a size equal to its own, a construct with the mecha subtype uses stabilized protomatter to warp itself and encompass every portion of that occupant. By doing so, it gains all of its occupant's anatomical extremities, powerful build, stability, natural weapons, extraordinary attack options based on its anatomy and adopts all of the occupant's natural attacks and movement speeds, in addition to its own.
Trap (Ex): An unauthorized occupant is held inside the construct as though paralyzed, but may attempt to take a physical action using the construct's body. For each action attempted, an unauthorized corporeal occupant must overpower the construct by succeeding at an opposed strength check. An unauthorized occupant may use the construct's body to break out of it with a Disable Device or Escape Artist check (DC equals 10 + 1/2 the construct's HD + its strength modifier).
Eject (Ex): A construct with the mecha subtype may forcefully eject its occupant as a free or immediate action, but only when directed to do so by an authorized user. An occupant that is forcefully ejected, may function like a weapon thrown by the construct, with a range increment of 10 ft, aimed at any other creature or location (AC 10) within range. If the creature strikes a wall or other hard and solid object before reaching the target, it takes damage equal to the construct's unarmed damage + 1-1/2 times the construct's Strength modifier. If the ejected creature strikes or lands on one or more creatures, they evenly split this damage and all other damage they suffer as a result. If the construct is destroyed with the occupant is still inside it, the construct simply falls away from the occupant, and its remains wind up around him or her, filling a space equal to its size.
Assign Operator (Ex): The moment it engulfs an authorized occupant, a construct with the mecha subtype automatically turns over full control of itself, including all of its abilities and movement speeds to that occupant. An occupant operating a construct with the mecha subtype, treats the construct, its senses, and all of its abilities as an extension of themselves, as if operating a mecha. While operating the construct, the authorized occupant always applies their own initiative count, base attack bonus, feats and skills, using the higher Strength score as found between him or herself and the construct. An occupant that operates the construct, does so using the construct's Dexterity score as well as its size modifier on attack rolls, opposed checks and skill checks. An operator wearing armor (assuming it fits) while within the construct, is still subject to its its maximum dexterity bonus, its armor check penalty and its rate of arcane spell failure.
Release (Ex): An authorized occupant my release themselves without harm from the construct as a free or immediate action, appearing anywhere within or adjacent to the construct's space. Unless the construct has already taken its turn for that round, it is then free to act immediately after its occupant's release action, as if the construct had delayed its turn.
Somatic Operations (Ex): An authorized occupant is always free to cast spells and effects with vocal components while inside the construct, along with other spell-like, supernatural abilities they might possess. If the construct's anatomy is compatible with that of its occupant, it may be actively operated by the occupant to in order to provide the somatic components necessary to produce a given effect, but without the Mecha Weapons Proficiency feat, those effects suffer a 50% arcane failure rate, or a 25% general failure rate for all other types of effects with somatic components.
Protected Occupant (Ex): The construct's occupant gains full cover and concealment relative to everything outside of the construct, and due to the insulating gravitational forces and layers of stabilized protomatter within the construct, he or she cannot be harmed while the construct is intact with at least 1 hit point remaining, even by incorporeal touch attacks.
Linked Senses (Ex): A construct with the mecha subtype transmits all sensory information to its authorized occupant through a mental link. Both of them may use construct's senses, each using their own skill ranks, feats and mental ability scores. If one of them perceives a threat, they all do. To catch any of them flat-footed, a creature must evade their combined notice. In addition, if one of them has a form of Uncanny Dodge, they all do.
Shared Saves (Ex): Whenever the construct makes a saving throw while it has a willing occupant inside of it, it does so using the best modifier as found between itself and the occupant. In addition, if one of them has a form of Evasion or Mettle, they all do.
Life Support (Ex): An authorized occupant can always breathe and speak through the construct normally, above or below water, and is not subject to inhaled or contact substances while inside. Only an authorized occupant may gain the magical benefit from any edible item the construct consumes.
Equipment Factors (Ex): A willing construct with the mecha subtype, can be affected by any beneficial spell or effect that affects objects. For the purpose of beneficial or harmless effects, the construct itself doubles as armor worn by both itself and its occupant. The construct's natural weapons, count as both natural and manufactured weapons. Much like an attended object, the construct may share the beneficial effects of applicable magic items, spells, spell-like abilities, supernatural abilities and extraordinary abilities (such as any spell resistance), that a willing occupant might have.Effective Hit Dice (Ex): For the purpose of effects that function based on an amount of Hit Dice, the construct may use those of a willing occupant, but only if higher than its own.
Effect Filter (Ex): A construct with the mecha subtype, as commanded by an authorized user, may permit any number of spells, effects and abilities that originate from its occupant, to pass through the construct as if it were merely equipment worn by the occupant. It may also permit any number of spells and effects that originate outside of it, to target and affect its authorized occupant normally.
Contact Telepathy (Ex): Creatures touching the construct can communicate with it telepathically.