For my Mews background, I started with the greens for the plants, then added the white for the flowers, gradually building up the purple, blue, and gold textures
The reality is this kind of replacement effect can lead to some uncommon and complicated interactions
Whenever a creature under your control would deal damage to a player, it also deals that much damage to the chosen player
At one point in the past year, it has seen sales as high as $1,300, and at the time of writing has a market price on TCGPlayer of $856.91
Once you get into the groove of your lock, use Penny / Professor Turos Scenario to clear clutter from your Bench, and take away easy Prize Cards from your opponent