Lets start with the original rules
In theory, you shouldnt be making any changes at all between games
It's been errata'd from a 'carriage' (which implies the creature represents the whole unit) to 'Horse', so I guess the flavour of the mechanic is the horses just being lazy until they are 'fed' with a creature
It's a great value if you draft and have your payment information at the ready
The illustrator's name, set symbol, card number, and card rarity were moved to the left above the copyright information
This can +2 to draw a card and scry two which is nice card flow, and then -3 to exile the top card of your library and then make a number of 1/1 flyers equal to the mana value, which is also very strong in Type Four with its elevated casting costs and low land count