Brain Game: Hoof on Roof
By BY

By changing one letter at a time to form different English words, and leaving all other letters in their original positions, convert REIN into DEER in the fewest steps possible. Good luck!
R E I N _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ D E E R
Here is a 6-step SOLUTION.
AN 8-STEP SOLUTION:
REIN > VEIN > VEIL > VEAL > DEAL > DEAR > DEER
Did you come up with a different or shorter sequence of words? Feel free to show off your work by commenting below.