I like to fill in blanks. When Avacyn and Griselbrand got sucked into the Helvault they mellowed out and grew to appreciate each other. They happily passed time in an endless dance party until outside meddlers blew up the party rock and the music stopped. They reluctantly parted ways. Later, Liliana Vess dispatched Griselbrand by popping his giant forehead zit with a claw-hammer.
Previous Helvault comic here.