Most important is that Evasive keyword, stopping any cards that dont have the keyword - or a similar ability - from even challenging him
Cards like Prosperous Thief and Heroes in a Half Shell reward your ninjas attacks and the combat damage they deal
Here's why: The Selection Pack randomly pulls from its own array of cards, 85 to be precise, of which only 17 are Shark cards that are actually useful/relevant, and most of that 17 are R and N rarity cards that can be easily crafted
Kindred cards also benefit abilities that care about the number of card types on individual cards, like how Rendmaw, Creaking Nest triggers when you play cards with multiple types
The Mycotyrant The Mycotyrant consistently creates multiple creature tokens in a dedicated self-mill deck
Three-mana 6/6 trample is no joke, even if Moon Girl and Devil Dinosaur won't be that all the time