Targum zu Bamidbar 2:25

The standard of the camp of Dan shall be to the north with their hosts; and the space of their camp shall spread over four miles. His standard shall be of silk of three colours, corresponding with the stones in the breastplate, chrysolite, beryl, and jasper; in it shall be expressed and set forth the names of the three tribes, Dan, Naphtali, and Asher; and upon it shall be expressed: And in his encampment shall he say, Return, O Lord, and dwell in Thy glory in the midst of the myriads of Israel; and upon it shall also be set forth the figure of a basilisk serpent. (Gen. xlix. 17.) The Rabba set over the hosts of Dan was Achiezer bar Aminishaddai,