This means that if your opponent has evolved Charmander into Charizard using Rare Candy, you'll send the Charizard card back to their hand while defeating Charmander with the 100 damage from the attack
The key thing to build around is the other than your hand line, so cards with foretell (Behold the Multiverse, Delayed Blast Fireball) and flashback (Think Twice, Galvanic Iteration) are excellent
turn: you can play Brook, who allows you to play a 3-cost or less FILM character, then play Nico Robin, who allows you to play a 2-cost or less FILM character, and then play Trafalgar Law, pay 1 for his ability, play a second Nico Robin, and play Law again
This creature gets +1/+1 as long as an opponent controls an Island
Perhaps leans into the theory of originating from employees