Tempest and Undertow
Mechanics by Fiat Victrix?
Speed +5 Acc +2 Dam +4L Def +4 Rate 6 Str Req. 2
Tempest has been known by many names-> the lover's blade, dark thunder, blood vengence. This blade is a terrible one, bound into eternal motion and hatred... except towards it's master. This blade had been forged from one of the most widely known killers of Onyx. Even in that land of death, she was particularly vicious and condemned. She had killed all those who she felt dared to touch on her man in such horrible ways that their spirits were set to hunting the isle as hungry ghosts. Now her fierce jealousy is centered around her wielder, the Crimson Marauder. Only in his hands does her howling voice and sweeping motions calm. Even sheathed at his hip she is not satisfied, needing not only his touch, but to serve his desires.
As she is in constant motion and she grows wrathful at any who would bring harm or otherwise touch her master, an attuned wielder who knows the Charm Vengeful Riposte (E->tAbyssals, page 170) may use it with Tempest without it counting as her Charm use for the turn. Upon dealing damage with each successful counterattack, Tempest gains +1 Def for the user's Ess in turns.
Speed +7 Acc +4 Dam +7L Def +0 Rate 5 Str Req. 2
Undertow is the twin of Tempest, forged at the same time. His deep growl reverberates in the bones and souls of those who face him. Once he had been the lover that Tempest had so jealously "guarded" in life. He had carefully shaped and beaten her in life to serve him, yet now he is enslaved to the one who carries him now. In counter to how she was never in control of herself nor her emotions, he was always calm and pure as the ice deep within the heart of the North. Such has stayed true through to his prison within the blade... yet he is far more unbalanced than his counterpart. Where she is unbalanced when away from her master's touch, he is calm when alone. In the hands of his master, he can not help but vibrate, growling out his impotent rage... and should any be so bold as to resist his edge and power, they only feed the anger and force within him. This rage will reach out to crush resistance, killing those fools.
The fury of the blade would be more legendary had many survived to tell of it. For each attack that is successfully defended against, whether from Undertow or Tempest, Undertow gains +1 Acc and +1L for the wielder's Ess in turns. This bonus can no more than double Accuracy or Damage.
Example in play-> Verdungo the Virile (Ess 4) faces off against one of those nasty ISPs. In the first turn he misses 3 attack, in the second he misses 1, in the third he misses 2, and it is now the fourth turn. He will start with +4 acc +6 damage, and will continue to roll higher as he misses attacks. At the end of the fourth turn, he loses 2 acc and 3 damage.
These blades can each be attuned for 5 motes each, but their additional powers beyond those granted by their soulsteel composition only apply when they are attuned together. Similarly the cost to attune each is lowered by one and they count as a single blade for purposes of blade summoning charms. In life, it was their relationship that fueled Tempest's bloodlust as well as Undertow's hatered of any resistance of his will, and so this dependance continues in their existance as tools for the Exalted.