Trusted traders or players
The drawback is that Thundering Raiju itself is only a 3/3, so players will be inclined to drop a counter on it with that first attack
Legolas, Master Archer Legolas, Master Archer works very well with auras, fight effects, or both (like Cartouche of Strength)
You can always cast zero-mana creatures for free so when they get bounced after being targeted with Cowardice on the battlefield and triggering Nadu, you can re-cast to repeat the process
When you do, add its power to this creature's until end of turn.) Enlist will allow you to add a different creature's power to your own, it will mean you can't perform those two attacks in a single turn but can boost for a lot of damage and is lower risk for your creatures
Belle is great for gathering more ink faster and being able to play more powerful cards in the early game