Since opponents will kill these things on sight, its good to have multiple cards that can do the same thing
Enchant creature Enchanted creature gets -5/-3
This keeps the initial experience much easier to grasp, while ensuring that the players will learn all of the game by the time they have gotten all the packs.
Im not sure these are going to be the best to bring newer commander players in on, but with guidance I think that they could be enjoyable decks for them as well
Since you can sacrifice any permanent, it works beyond creature-based sacrifice decks to support sacrificing lands or sacrificing artifacts like Ichor Wellspring
Rex, Cyber-HoundRex, Cyber-Hound (Helms 646 Decks, Rank #1,257