Study is a very good card quality spell but it is far less exciting in blue where you are spoilt for choice than it is in red, flashback aside
Spider-Ham, Peter Porker swings in as one of the best animal leaders in Magic, and you'll likely need to go the Temur route to benefit from the otters included in it's May-Ham list
Then if you've done all four this turn, transform Avatar Aang
For me its reached a point where I literally just have a preset document where all the attack, power/ability, icons and other card elements are locked in, allowing me to swap things in and out at will
Lo and Li, Royal Advisors Lo and Li, Royal Advisors are mill on demand, very similar to Oona, Queen of the Fae
A benefit of reconfiguring Rabbit Battery onto a creature is that if a board wipe happens, Rabbit Battery will simply return to being a creature since it's considered an Equipment while attached to a creature