(SG-1 xover) A Goa-uld tries to posses Xander on Halloween

[ladyhatshepsut.livejournal.com]

I'm trying to locate a Buffy/Stargate SG-1 crossover that begins with O'Neill and team chasing a Goa'uld through the streets of Sunnydale (or are they in Cleveland).  It tries to possess Xander who's out with several mini-Slayers dressed as pirates for Halloween, but is pushed out by Willow's anti-possession spell.  After some discussion Xander agrees to go to the Mountain so SGC can figure out why the Goa'uld couldn't take him over.  Hellmouth business brings him back home to his house full of mini-Slayers.  For reasons I've forgotten the NID (I think) stage a midnight raid on the house and one of the girls is killed.  Heart-sick and enraged, Xander plans revenge until the spirit of the dead Slayer talks him out of it.  (I think Faith and Spike are at the house and I think I recall Dawn at the hospital with the dead girls housemates.)