Do Terradons roll 3D6 and discard the lowest for their flees? Do they make a dangerous terrain check for fleeing through other units/environment? Thanks!
Yes, terradons do flee along the ground and roll 3d6 and pick the best two when they flee since they are "flying cavalry" (CRB p. 70). Also, they have to take dangerous terrain tests when fleeing through enemy units or terrain other than open terrain. The one exception is for forests since they have the forest strider special rule (p. 76 CRB and the FAQ).