The Metal Tribe was a fairly large tribe that used brute strength to go into war.
The Metal Tribe resided in Pitchbottom Cavern (before the meteor landed) and were the only known fifis to get down to the bottom and come back up to tell the tale. They went to war with the Ice Tribe because of a magnetic force at their base. Eight attacks were launched and they finally gave up and never bothered them again. One or two metal fifis were often found in the Earth Tribe's tunnel system but there is no clue how they got there.