If you have questions that are not covered here, they may have been asked or answered before in one of the below resources
If you look at our level-up creatures, you'll see that almost all of them start off underpowered based on their cost, before eventually becoming good or even great, assuming we can dump a bunch of mana into leveling them up (without our opponent killing them in response)
Other Zombies you control have vigilance
This is a new mechanic debuting in Innistrad: Crimson Vow that allows you to pay an alternate cost for the card in order to become an editor and gain a version of the card that is the same, but you have to remove the words in the brackets
These are typically great uncommons that really drive you towards playing a particular color, like build-arounds and good removal, as well as very powerful commons
I also tried to prioritize ones that you might actually play with