Other sets carry strong sealed values too: a sealed EX Dragon Frontiers booster box has been quoted at around $135,000, which shows how even post-vintage boxes hold serious value when they stay unopened
There's no limit to the number of trainer cards you can have in your deck, but around 20 is usually a good amount
Green decks almost always have the biggest creatures, so you dont need to worry about your opponents drawing too many cards off this mana and card advantage engine
A mono-black deck won't have access to something like Golgari Grave-Troll, but it can still use Stinkweed Imp and Golgari Thug to give some punch to Songs of the Damned
Azusa's ability is cumulative with other effects that allow you to play additional lands, such as that of Wayward Swordtooth
You would play a turn five Undo, and win the game