Abraham Benrubi played a troll who was released from a crystal when a spell Willow was casting was interrupted one too many times by Anya. Coincidentally, Anya turned this particular troll into a troll. Troll tears up the Magic Box and escapes. Troll goes on rampage and requests ale and babies from Xander and Spike. Buffy appears, and fighting ensues.
Troll tears up the place and escapes.
Willow and Anya go back to the Magic Box to find a spell to send him back, but he appears before they find one. Xander appears and tries to take him on single-handedly with the usual result. Before he has to choose, Buffy shows up and starts taking names. The non-combatants quickly realize that his strength comes from his hammer, so Buffy separates him from it. All in all, it was a fun episode, but didn't really move things along much, story-wise.