Power-boosting spells like Colossal Might or Might of Oaks can serve double-dutyyou can boost your own Ring-bearer to allow it to be blocked, or if you want to disable a potential small power blocker, you can target your opponents creature with it so your Ring-bearer can slip past
Kuzan specifically draws you a card as soon as its played, and can reduce characters cost when attacking, synergizing perfectly with other black cards with K.O
I recommend using a jig like this
Unless you have some turned-face-up synergy in Rakdos that I dont know about, Arno is better off in the 99 of your Altar Ibn-La'Ahad deck
As I mentioned, this list isnt entirely exclusive because some cards dont have a market price yet, so always give an eye to current listings when trying to evaluate your booster pack pulls
In short, we looked back at all the things we'd done with vehicles and knew the importance of a one-to-one relationship between one or more creatures and a vehicle