While there isnt really a bad time to play cards like Mist Dancer or Lord of Atlantis that can help you evade blocks, you may want to hold them back if youre close to finishing someone off
By the time you put in enough creatures to make your noncreature spells cheaper, you run out of room for the noncreature spells
We were also free to experiment with putting cards in the booster that weren't game pieces
For example, Tekuthal, Inquiry Dominus mentions proliferate, but isnt a proliferate card for the purposes of this list
Again, it assumes you have a decent amount of mana, but if you've got it, this is a flying threat that can Attack on the first turn it gets played thanks to Haste
Cultivator Colossus's power and toughness are each equal to the number of lands you control