We are currently sitting with Duress, which is great in most formats
Aside from just filling your hand with more great Knights with this trigger, it can also be used to find powerful cards like Sword of Feast and Famine and Animate Dead
Incapsula incident ID: 1225000270075694866-278390507372611282
Magnemite can be searched from the deck and put into play by Tandem Unit, and the option to use Overvolt Discharge means Trainers do not need to rely solely on favorable hits with Electric Generator to accelerate Energy onto the battlefield
Eventually, you can go to combat, get all those myriad triggers on the stack, and then cast one final instant to turn Muddle into whatever it is you actually want to copy
If an Aura is being put onto the battlefield at the same time as a creature, that Aura can't enchant that creature