Through trickery (and a bad perception rolls by me and my group) a newly discovered enemy has acquired a material link to my character, I.e. A drop of blood. I am a relatively new Shapeshiter Mage, and I wonder what can be done to defend from it. So far, I've mostly found information on how to use one against someone rather than how to defend against a spell cast by one.
Thanks!
PS... Any suggestions on an alias (aka Street Name) for a Black Panther (basically a black jaguar...it's possible, I looked it up!) shapeshifter from Amazonia? He is primarily a combat Mage and follows the Aztec Tradition (not blood magic). His mentor spirit is of course a black panther (modeled on lion), so he tends to be somewhat aggressive. For some reason I'm just not coming up with anything that I really like.
The answer to your question is. . . get new DNA. Or really good Counterspelling. Also, even with refrigeration/magical preservation, a tissue sample decays with time, a single drop of blood shouldn't last more than a week. Even then, it's only good for one ritual, even if the ritual has to be aborted. (Street Magic, pg. 29)
Best bet, therefore, is a combination of "wait it out" and "go on the offensive". Send a watcher spirit to keep tabs on the guy, they're cheap, plentifully available and have the search power. Once you know where he is from your watchers, send bigger, badder spirits after him, or arrange a run against him yourself. Heck, a watcher spirit spying on him (he can't astrally perceive all the time, and if he's persistently bothered by your spirits, he's not casting ritual spells at you) could tell you when he enters a magical lodge from which he could cast a ritual spell. The watcher spirit shows you how to get there & you hit him hard mid-ceremony.
Certainly fits the "aggressive" description you provided.