The mana is a little unstable, in that there are only thirteen black sources and there are five lands that dont cast Steel Leaf Champion, but Glowspore Shaman and Llanowar Elves both help with casting Steel Leaf Champion and you dont strictly need black early
As stated, there are three different types of cards that may be included, Characters (Glimmers), Items, and Actions
Legendary Creature - Elder Dragon Color tag templates(None) Shalai, Voice of Plenty Flying You, planeswalkers you control, and other creatures you control have hexproof
One match of Modern is roughly estimated to be 20 minutes long
Luckily, Magic has hit it out of the park with things like the Cactuar card's somewhat controversial ability to deal 10,000 damage
Now consider discounted prices based on what you may already have in your collection, and prices go down considerably