WeaponsThroughout XIII-2, Serahís weapon is the bowsword. Serahís bowsword is actually a transformed Mog, and doesnít exist on its own - the one time Serah is without Mog, her bowsword is more an echo and reflection of her will than a physical thing. Mog and his bowsword capabilities was first presented by Lightning to Noel in Valhalla as a gift for her sister, as her aide and guide.
(Also, at the end of a battle, Mog changes back to his regular moogle self and Serah hugs him as part of her victory pose which is as cute as it sounds.)
As the name suggests, the bowsword is both a bow and a sword, switching appearance as need requires, but itís explicitly both - this is because XIII didnít believe in hammerspace weapons unless you were Hopeís boomerang - and the damage dealt by the bowsword remains the same no matter which mode itís in. As weapons go, itís definitely different, but for Serah, its actually pretty perfect.
The default bowsword, which is also the same bowsword featured in all promotional and concept artwork where present, is known as Starseeker. Its colourscheme is a combination of purples, pinks, and whites, which is perhaps an obvious choice, given this is also Mogís colour configuration. Starseeker shares its name with (and is potentially named after) a Keyblade from the Kingdom Hearts series, but even so, the name choice makes sense, given that Serah travels up and down the timeline, the stars, seeking something, someone. Upgrades to Starseeker do indeed exist; these can either be bought from Chocolina or found in the world itself. Iím always pretty reluctant to change weapons I like the look of, or ones that have significant meaning in plot and cutscenes, even if better stats are on offer, so any changes to the Starseeker I used were sporadic at best. Be assured that there is a long list of weapon upgrades for Serah - you can find most of them, as well as how to attain them, over at the FFWiki.
The ultimate version of the bowsword is known as Arcus Chronica, which I donít recall, as Iím much more familiar with Odinbolt, since I blitzed through the game for fragments so fast that Odinbolt was already superior to Arcus Chronica by the time it was available to me. Go figure. Though Arcus Chronica is Serahís ultimate weapon, Odinbolt feeds off paradox energy and the more fragments you have, the stronger it gets - if youíre dutifully collecting fragments when Hope develops it and gives the player the choice between a paradox weapon for Serah or Noel, itís worth the investment. You can get the one you reject later by playing slots at Serendipity, and naturally I chose Serahís weapon first because why wouldnít I.
Despite using Odinbolt a lot, Starseeker is still my favourite variant of the bowsword, at least aesthetically.