Alistair

Alistair is an English nomadic vampire. He is described as tall and dark haired, with a misanthropic, brooding personality. Alistair has a deep mistrust of all authority and although he counts Carlisle as his closest acquaintance, he doesn’t visit more than once a century. He has the power to track people and feels an elusive pull towards a persons location which helps him find them. He ran away before the Volturi arrived to accuse the Cullens, despite his promise to act as a witness on their behalf.

Breaking Dawn
Alistair appears in Breaking Dawn, briefly. He agrees to be a witness for Renesmee, but only grudgingly. He kept to himself through the month of waiting, mostly staying in the attic which was his 'favourite place to sulk', and disappeared before the Volturi arrived.