They are Observers and when there is a difficult call that the players can't resolve on their own, they will ask the Observer to make the call. Observers are well versed on the rules of the sport and their opinion on a call is regarded as the most accurate on the field
That's something I've noticed watching ultimate videos... it's seems like people spike the disc a ton. In general, unless it's a catch that God himself would have trouble making, it isn't really spikeworthy...
They have a ref. If the game is big because the refs going to have to make decisions on either the yellow team wins or the black team is still tied. So they need to make executive decisions. But like when I play we have no refs.
