Mine's also Metronome-based... Battle Factory, fourth run-through. I had a Chansey, Scyther, and a Weezing I think.
The basic jist is, it was Chansey vs Lickitung, and Chansey's metronome had used Ingrain, so it was stuck there. When I ran out of Metronomes leaving Lickitung with red HP, it turns out Chansey's remaining moves were Refresh, Minimize and Defence Curl.
Lickitung had Brick Break, Wrap, and two non-damaging moves.
One of Chansey's Metronome moves was Ingrain, so it was stuck there. It was also holding Leftovers. Lickitung rarely used Brick Break, and when it did Chansey had restored all it's HP in a few turns thats to Ingrain + Leftovers.
I was left doing all these defenive moves, effectively leaving the match as a stalemate, so I ran out of patience and turned my DS off. >_>