The missing cards needed to complete this perfect master set are not included, as the original artist never received a copy when each piece was originally sent out
Ideally, in the mid-game, the second stage of the game, you want to be able to both develop your battlefield and ramp at the same time
Ill use this spot to mention Lilysplash Mentor and Abuelo, Ancestral Echo
Note that this works for when any creature attacks, not just yours, so when someone attacks you and triggers a defensive card you also net the trigger twice, so you could play this in a Pillow Fort deck build around things like Cunning Rhetoric and Search the Premises
But this cards effect is symmetrical, meaning when you damage your opponents creatures, you are giving your opponent, the creatures controller, a massive card advantage