I definitely disagree with RGSAlex here - I think Counterspelling is valuable in cases where there is an enemy mage in a relatively secure position dropping battlemagic - or Chaotic Worlds - on the party. "Geek the mage first"<em>is</em>very strong shadowrunning advice, but shooting a mage in the face doesn't do anything about the stunball that already went off.<br/><br/>However, I'm not going to say to take my advice over his - just putting the pros and cons of alternatives out there - because yeah, multiple mages will chew through Spell Defense.<br/><br/>A strong active magical defensive option might be to use Mana Static to effectively nullify the ability to efficaciously do magic at all in an area - I think I've heard of builds that relied on a mage tuned for such to ensure a run would be non-magic, and was otherwise a utilimage.  Or, y'know ... Stunball.  Or the AoE Euphoria spell.