Without describing it too particularly, I had a legacy item that leveled with the user, but then we played to epic levels (30+) so it was rather powerul magic item - in my case a ring. Everyone in our party got a different legacy item, some were weapons, some wondrous items, mine a ring. It was the homebrew item that got my thinking cap on how to properly design a legacy item for publication - and right now the last design look over is being done on Ancestral Relics (that's what I call them) for the Kaidan GM's Guide in its final wrap up before release.
Unlike Weapons of Legacy there is no expenditure of gold pieces nor experience points to activate powers (both stupid concepts IMO), rather Kaidan's honor mechanic is tied to it, plus one's level, and finally an event trigger - some required action: an obstacle overcome, an oppponent of appropriate level beaten, or some other specific action based on the item and the class of the person possessing it. Oh, since it's tied to the PCs heritage, it only functions as a masterwork mundane item in the hands of someone not of the correct heritage. An ancestor's soul powers the item.
I once gave one of my players a shape-shifting sword. As a full round action it could shift into any reasonably sized item(I think this was only our second game ever, and the first one I ever GM-ed so we would discuss weather or not what he wanted to do was allowed). I believe it also could was a +8 item that he could modulate the enhancements on it as-well.
@Kenjishinomouri - my real middle name is Kenji... I meet so few.
This thing here — an item set consisting of five items (two gauntlets, pair of boots, breastplate, helm). It was one of the major focusing points of an entire years-long campaign. (Detailed item powers redacted for length.)
The Grand Sultan of the efreet wore the Armor into battle during his campaign of interplanar conquest, but he was defeated by an alliance of Good-aligned heroes and creatures. The Armor was scattered across the planes; but many years later, parts of it began to find their way to the Material Plane...
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The Armor of the Grand Sultan: Created by the late, half-human Grand Sultan of the efreeti to grant himself power and control over his recalcitrant subjects, and composed of several semi-independent parts, this armor is impressive indeed. Though the individual and synergistic powers of the set pieces are described at length below, wearing the entire armor grants several formidable and unique powers to its fortunate owner.
For one, the unified armor magically binds itself to its wearer, and maintains this bond regardless of distance. The first person to don the entire set becomes the armor's recognized owner; thenceforth, he may take a standard action to recall the armor to him, provided he is located on the same plane as all its parts. (Otherwise this power functions as the called armor enhancement.) The only way to unbind the armor from its owner is to kill him, then scatter the armor's parts throughout the planes.
When the entire armor is worn, all the onyx gems set into it (one in each glove and each boot, one in the breastplate, and three in the helm) are searing hot to the touch, and a bright fire can be seen burning in their centers.
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Breastplate: This +5 breastplate is made of brass, but due to the intense process of its creation, is hardened to provide a +5 bonus to AC (+10 total with the enhancement bonus). The entire armor provides a +7 bonus to AC (+12 total with enhancement bonus). The surface is engraved with various arcane symbols describing powerful abjurations, and is decorated with flames dancing around the armor's edges. A large onyx gem is set into the center, directly above a human wearer's heart.
The breastplate's primary function being protective, it has a variety of functions related to shielding the wearer from the fiery doom that the other parts of the armor are designed to inflict.
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Helmet: This elaborate brass helmet, which is set with three onyx gems, seems mostly decorative, and does not provide much protection. It is crafted, however, in such a way as not to obscure vision, and it is a comfortable fit for any Medium-sized wearer. When worn, the helm appears to burst into flame, giving off a continual flame effect, and making it effectively impossible to hide. This effect cannot be dispelled, and is not suppressed in any sort of magical darkness.
The simplest power of the helmet becomes obvious the first time the wearer lights a bonfire; the helm permits the wearer to see through mundane or magical fire and smoke of any kind perfectly; opponents obscured by such smoke do not benefit from any concealment against the helm's wearer.
The primary purpose of the helmet is control. It serves to focus the energies of the rest of the armor into coherent powers. When worn separately from the entirety of the armor, this controlling magic attempts to exert itself in strange ways.
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Boots: These tall, almost knee-high boots are made of brass, and engraved with images of fire and smoke. Though they are entirely metallic, they are nonetheless comfortable for any Medium-sized wearer. A small onyx gem is set deep into the heel of each boot. When when the boots are worn, small wisps of dark smoke rise from them continuously, giving off a faint sulfuric odor.
Inspired and powered by the Paraelemental Plane of Smoke, the boots were designed by the Grand Sultan to aid in travel and, should the situation require it, escape.
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Gloves: These brass gauntlets are too thin and flimsy to provide any real protective value, and a character wielding them is not considered armed. However, they are quite ornate, and a highly polished black onyx gem is set into the middle of the palm of each glove.
The purpose of the gloves is offensive in nature: the Grand Sultan imbued with them with the ability to generate elemental energy. The Quasielemental Planes of Radiance and Ash are the inspiration and source of the gloves' power.
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