Anything that makes artifact creature tokens is needed, and Servos can fit the bill, especially since Cayth grants fabricate to other cards
The differences here are primarily in sideboard construction, as the first list is using stuff like Tormod's Crypt as additional graveyard hate, while the second has some more traditional Wasteland + Strip Mine action for dealing with cards like Tabernacle
Bruse Tarl, Boorish Herder Bruse Tarl, Boorish Herder, aside from the Magic 2011 titans is one of the early creatures to have an effect upon both ETB and attacking, and what an aggressive effect it is
Ramp Whether it's getting lands out faster, or playing creatures and artifacts that generate mana, you need a way to 'ramp' - that is, to rapidly increase your available mana, beyond playing your one land a turn