Links to start with
Some background here: In the main Gundam continuity, the most dangerous pilots on the battlefield are psychics called Newtypes, who can predict their opponents' moves and control special mecha/weapons. The most famous of these weapons are bits/funnels, swarms of insanely small and fast attack drones controlled by the pilot's thoughts.
And that's where the Unicorn Gundam comes in. When a Newtype comes within range, its NT-D (Newtype Destroyer) system activates, dramatically boosting its power. In addition, most of its body is composed of the transmitters used in Newtype weapons, allowing it to produce signals far stronger than its enemies. In other words, it can take control of any Newtype weapon brought within a certain distance of it automatically.The NT-D system in action
Here's my attempt at translating this into D&D terms.
Detect Magic (Su): At 1st level the barbarian is under a continuous detect magic effect with a caster level equal to his character level. Unlike a normal detect magic effect, it takes the form of a sphere of Close radius (25ft +5ft/level) centered on him. At 7th level the range of this ability increases to Medium (100ft +10ft/level) and at 14th level it increases to Long (400ft +40ft/level). As a standard action the barbarian can extend this effect to double its normal range for 1 round. As a full-round action he may extend it to triple its normal range.
Mage Destroyer (Ex): At 1st level, whenever the barbarian's detect magic detects a spell or spellcaster he may choose to enter a state which provides a +2 bonus to all ability scores, +1 per five caster levels of the highest-level spellcaster in range. While this state lasts he is compelled to kill all spellcasters within range using any methods available to him (his ability to concentrate is not hindered). This state lasts for a number of rounds equal to 3 + his Con modifier, but he cannot leave it prematurely unless he succeeds on a Will save (DC = 10+caster level of the highest-level spellcaster in range).
Bonus Feats: At every odd level the barbarian gains one bonus feat from the list avaiable to fighters. He must meet the prerequisites for this bonus feat as normal.
Control Spell (Ex): At 2nd level, while using Mage Destroyer the barbarian is considered to be the original caster of any spell within the range of his detect magic ability, as long as its caster level is below or equal to his barbarian level. Such a spell increases in caster level to his barbarian level if lower, and its owner no longer has any control over it. At every 4th level, his effective barbarian level increases by +1 for the purposes of this ability. The barbarian gains full knowledge of the functions of any spell he has hijacked in this manner. The barbarian can maintain concentration on such hijacked spells as a free action.When the barbarian leaves Mage Destroyer state, all spells he is controlling end immediately. The barbarian cannot control magic items in this fashion, except for spell trigger and spell completion items (since their effects are spells).
While controlling a spell creatures summoned or controlled by the spell consider him their new master, he may change the target of any spell which allows changing targets (personal spells remain with their owners rather than transferring to him) or dismiss any spell which can be dismissed. He may also choose to invert the effects of a beneficial spell or cause it to provide the worst possible result (eg. mage armor would provide a -4 penalty to AC, false life would reduce hp, and a wizard under the effects of blink would blink while attacking but not while being attacked). When affected by an instantaneous spell or when an instantaneous spell is cast within range, he may choose for it to simply fail. The barbarian cannot take control of nonmagical attacks created by spells (eg. a telekinetically-hurled rock or an orb spell) unless the spell is cast within the radius of his detect magic effect.
Flight (Su): At 6th level, while in Mage Destroyer state the barbarian gains a fly speed equal to his land speed with perfect maneuverability.
Greater Magic Weapon (Su): At 8th level, while in Mage Destroyer state all of the barbarian's weapons are under the effects of a supernatural greater magic weapon effect (caster level equals his class level).
Telekinesis (Su): At 10th level, while in Mage Destroyer state the barbarian can use telekinesis as a supernatural ability at will (caster level equals his barbarian level), except that the range is equal to the range of his detect magic.