You could just plop them down and then play all of the Rakdos Forced Combat cards, such as Goblin SpymasterGoblin Spymaster, Fumiko the LowbloodFumiko the Lowblood, Disrupt DecorumDisrupt Decorum, War's TollWar's Toll, and Goblin DiplomatsGoblin Diplomats, then just sit back and watch the carnage unfold
You can buy them with the tin, or in a Tuck Box instead
In game three I dont see a single Merlin, Rabbit until its almost over
Blighted Agent/Skithiryx, the Blight Dragon + big creatures under Mimeoplasm: This is what I would consider your main means of knocking players out
While it might sound silly to make your opponent draw a potentially useful card, the steep number of 20 would all but guarantee them milling out and being unable to do anything with whatever they draw