This is a review request for a warbow, intended for the Pathfinder system. The purpose behind the creation of this particular item was to allow the player to quest for a magic item that was not essentially useless at higher levels, but rather gained abilities as the PC gained levels and powers. It is a single occurring item, could possibly be considered as an artifact status, even though it is intended to be available starting at a low level, slanted towards a horizon walker or similar concept. Description and capabilities are as follows:
[Insert name here] was a distinguished ranger, well known for his willingness to protect those around him when the cause was just, regardless of the consequences to himself. Many of the tales that have grown around him have reached the status of unverifiable legend, but it is certain that his bow was a feared weapon among the unjust. It is rumored that he even ventured onto the Abyss and other planes to retrieve people stolen from their land.
Sometime after he retired, he returned to his woodland home to find his wife murdered, and son missing from their house. Taking up his bow once more, he ventured forth to rescue his son. It is unknown what actually happened, but his son was returned, and [...] and his bow were never seen again. Most believe that he either perished, or made a trade with an infernal being to exchange himself for his son.
Many people claim to have either seen or wielded his bow after that, but none of these have been confirmed, and few even believe that the bow existed, counting it as another fantastical tale that surrounds his legacy.
DESCRIPTION
[Insert name here] Warbow is dark wood intricately carved with arcane runes, and glows with a faint amber glow in dim light. A white leather grip is secured to the bow with three silver bands, one each at the top, middle and bottom of the grip. To successfully utilize [...] Warbow to its fullest potential, a character must fulfill the following requirements:
Feats Exotic Weapon Proficiency, Far Shot*, Planar favored terrain** (Edit for clarification: The planar terrain relates only to the planar shift aspect).
Skills Craft (bowyer) 4 ranks, Spellcraft 4 ranks
ABILITIES TABLE
Character Level Weapon Level Weapon Effect 1st - 2nd 1st +1 adaptive war bow 3rd - 4th 2nd Activation ring spell storing, minor 5th - 6th 3rd Enhance arrows 7th - 8th 4th Minor displacement (as blur) 9th - 10th 5th +1 adaptive distance* war bow 11th - 12th 6th Activation ring spell storing, regular 13th - 14th 7th Plane shift, ** 3/day 15th - 16th 8th Imbue arrow 17th - 18th 9th Phase arrow 19th - 20th 10th Activation ring spell storing, major 1: +1 adaptive: At first level, the bow gains the +1 adaptive quality. Bow is +1 to hit/damage, and Strength bonus applies as well.
2: Spell Storing (Su): At third level, activation of the first ring occurs. This ring activates and functions as a ring of spell storing, minor.
3: Enhance Arrows (Su): Each non-magical arrow fired gains +1, and one of the flaming, shock or burst attributes.
4: Minor Displacement (Su): When wielded, the weapon distorts light as a cloak of displacement, minor, resulting in 20% miss chance on attacks against the wielder.
5: Distance (Su): Every arrow fired by the bow gains the distance quality. *Note: For this to be used, wielder must have the Far Shot feat. If this is not available, this ability lies dormant until it is acquired.
6: Spell Storing (Su): Activation of the second ring occurs. This functions as a ring of spell storing, regular.
7: Plane Shift (Su): At 13 th level, the leather wrap darkens and close inspection reveals swirls. This can be used to activate and take up to 8 linked people as in the spell plane shift. If the shift is to a favored terrain, the bow grants the wielder the ability to natively survive while in possession. In addition, the accuracy is 1-10 miles from target. In other planes, normal accuracy and conditions apply. **Note: The wielder must have a plane as a favored terrain. If this is not available, the ability lies dormant until it is available.
8: Imbue Arrow (Su): The bow grants the ability to infuse any non-magical arrow with either a known or stored area of effect spell. This spell will activate on any hit. If the result of the attack is a miss, the spell is lost without activation.
9: Phase Arrow (Su): The wielder can launch an arrow 2x per day at a target known to him within range, and the arrow travels to the target in a straight path, passing through any nonmagical barrier or wall in its way. (Any magical barrier stops the arrow.) This ability negates cover, concealment, armor, and shield modifiers, but otherwise the attack is rolled normally.
10: Spell Storing (Su): Activation of the third ring occurs. This functions as a ring of spell storing, major.
Aura moderate abjuration; CL 12th; Craft Magic Arms and Armor, creator must possess the arcane pool quality; Price +5 bonus.
I would like to determine if this is a logical progression, or if it is not enough in the beginning progressing to overpowered at the high end?