3-7 Uncommon cards
Luckily, were in green, so we probably ramped into those lands
1 Elvish Mariner
However, there are enough lower rarity Cats that also slot nicely into virtually any white deck (Felidar Savior is a solid choice for green/white +1/+1 counters or black/white lifegain, for example) to make Arahbo a worthy buildaround, making this Cat lord a crossover hit
For example, if you control Johann, Apprentice Sorcerer ("Once each turn, you may cast an instant or sorcery spell from the top of your library") and Promise of Aclazotz is on top of your library, you can cast Foul Rebirth, but not Promise of Aclazotz
The ultimate, which isn't something you have to build up to, creates an emblem that keeps you safe as long as Gideon is there to protect you