Zetalpa, Primal Dawn: The main target for our Build-a-creatures, double strike and flying giving us good attacking power and indestructible giving us good evasion, which is the most important type of keywords to give.
Banehound: haste creatures are important for Urborg scavengers as it lets them get multiple stuffing targets in the same turn, and of course attacking the same turn is important. Lifelink also helps us race aggro decks
Striped Riverwinder: Our second most important stuffing, as hexproof in combination with indestructible makes our build-a-creatures almost impossible to kill for most decks, and being able to enter the graveyard with cycling makes it super convenient
Hazoret the Fervent: Other then two relevant keywords, haz makes a decent threat herself, as it’s pretty easy to go hellbent with our discard and overall cheap curve for this deck.
Samut, Voice of Dissent: Mainly here for double strike and haste, never really going to be casted like with zetalpa but is possible with fable.
Murderous Rider: Another double duty stuffing, this card is very helpful for creature based decks for the additional removal and lifelink for himself and our build-a-creatures.
Nighthawk Scavenger: A stuffing that can be reasonable threat on his own and can stop most creatures in their tracks.