Braingeyser will let you refill your hand as needed at this point, and you should be able to generate infinite mana, infinite Shivan Dragons, or the opportunity to fire off infinite Braingeysers at your opponents
Monumental Corruption can also draw you a fistful of dollars cards if you have the life to spare
As a very general rule for Limited, I would look to play something like this: 1 mana: 02 2 mana: 46 3 mana: 35 4 mana: 24 5 mana 13 6+ mana: 02 That's far from hard and fast, but it's a good place to start
May contain these cards: ECL 1268
If this wasnt good enough, even its main downside can be mitigated thanks to abilities like Proliferate and Time Travel
Theres a menacing look in Sephiroths eyes, and he looks like hes about to swing his sword down on the camera