Gozer the Traveller will come in one of the pre-chosen forms.

During the rectification of the Vuldronaii the Traveller came as a very large and moving Torb.
Then of course in the third reconciliation of the last of the Meketrex supplicants they chose a new form for him, that of a Sloar.
Many Shubs and Zuuls knew what it was to be roasted in the depths of the Sloar that day I can tell you.